DTC P1237 & P0453 Blown in tank fuel line.

[99lightning_svt]

I need a bit of help guys.

I've been having issues with the car pulled those two codes. Dropped the tank, found the fuel line from the pumps to the hat had blown. The power wires were also a bit burnt... (Stock Cobra hat with two AEM 50-1200 320 LPH)

Here are my questions for the guys in the know.

What fuel line should I be using from the pumps to the hat? The fuel lines I have now are not the clear ribbed lines, I really need something that can make that 180 turn better without pinching. The clear lines would probably work but finding them would be difficult.

Should I replace the power wires all the way back to the PDFM or whatever you call it? (Long day)

Will this fix the codes listed or should I be looking for another issue as well?

Thank you for your help!

 

[MG0h3]

Geez I can't even remember what my fore hat to pumps has. I almost thing its from the sock to the pump to the hat with no external lines. I recall the ribbed lines on my factory pump.

Regarding the wiring. Whats your total setup? Generally burnt means resistance.

 

[99lightning_svt]

I believe a shop incorrectly wired my BAP, I don't drive the car much so the details are fuzzy. Less than 500 miles in the past 5 years...

I had some fried wires to the BAP that I have since corrected. I believe this is the point at which the wires in the tank must have been damaged.

See link: https://www.svtperformance.com/foru...d-wiring-and-melted-fuse-i-need-help.1134980/

I removed the wires from the hat tonight at the connector and resoldered new wires to the pumps. My hope is I can reattach the end connectors to the bridge by bending the same crimps back down and soldering for good measure.

If I need to rewire the entire system from the hat to the BAP I can and will. The wires look good but its hard to tell without stripping the cover. I'm sure there is a test I can do with a voltmeter but I will need to research.

My total set up for fuel is 80lb injectors I believe, a BAP, Modified FPDM, stock lines. I'm under 600hp so I should be well within the capabilities of what I currently have.

If... i can get it to run correctly.

Thank you,

 

[hotcobra03]

you may have found issues,but was in manual tonite.

here is what that gives on codes.being a paste and copy it will give all of the pintests.just start at given step number.

po1237.start kb47

2003 PCED OBDII
SECTION 5: Pinpoint Tests
KB: Fuel Pump Driver Module (FPDM)

KB: Introduction
KB1 DTC P1233 OR P1234: IS DTC P1233 OR P1234 PRESENT IN KEY ON ENGINE OFF SELF TEST
Is DTC P1233 or P1234 present in Key On Engine Off Self-Test?
Yes No
A hard fault is present. GO to KB2 . The PCM is now receiving a signal from the FPDM. One possible cause of the DTC P1233 or P1234 is that the IFS switch was tripped, then reset.

If engine is now a no start:

Disregard the DTC P1233 or P1234 at this time. RETURN to Section 3 and CONTINUE as directed. After servicing the no start, to diagnose intermittent causes of the DTC P1233 or P1234, RETURN to GO to KB25 .

If engine will start:

GO to KB25 to diagnose intermittent condition.

KB2 DOES THE ENGINE START?
Does the engine start?
Yes No
GO to KB15 (to check the FPM circuit). VERIFY IFS switch is set (button depressed). If OK, GO to KB3 .

KB3 CHECK POWER AND GROUND CIRCUITS TO FPDM

• Disconnect FPDM.
• Key on, engine off.
• Measure voltage between the FPDM PWR pin and ground pin at the FPDM harness connector.

Is voltage greater than 10.5 volts?

Yes No
Key off. REPLACE FPDM. GO to KB4 .

KB4 CHECK POWER TO FPDM

• Key on, engine off.
• Measure voltage between the FPDM PWR pin at the FPDM harness connector and chassis ground.

Is voltage greater than 10.5 volts?

Yes No
REPAIR open ground circuit to FPDM. KEY OFF. No power to FPDM.

For Escort, Mustang:

GO to KB5 .

All Others:

GO to KB8 .

KB5 CHECK B+ VOLTAGE TO CCRM PIN 11 (FPDM POWER SUPPLY RELAY)

• Disconnect CCRM.
• Measure B+ circuit voltage at Pin 11 of the CCRM harness connector.

Is voltage greater than 10.5 volts?
Yes No
For Mustang:

GO to KB6 .

For Escort:

GO to KB7 . VERIFY integrity of related fuse. If OK, REPAIR open B+ circuit. If fuse is damaged, CHECK B+ and FPDM PWR circuits for short to ground before replacing.

KB6 CHECK GROUND CIRCUIT TO CCRM PIN 18

• Measure resistance of ground circuit between CCRM harness connector Pin 18 and chassis ground.

Is resistance less than 5.0 ohms?
Yes No
GO to KB7 . SERVICE open ground circuit.

KB7 CHECK FOR OPEN FPDM PWR CIRCUIT

• Measure resistance of FPDM PWR circuit between CCRM harness connector (pin 5) and FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
REPLACE CCRM. The FPDM PWR circuit is open. GO to KB13 to help isolate fault.

KB8 CHECK B+ VOLTAGE TO FPDM POWER SUPPLY RELAY

• Disconnect FPDM power supply relay.
• Measure B+ circuit voltage at the FPDM power supply relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
GO to KB9 . VERIFY integrity of related fuse. If OK, REPAIR open B+ circuit. If fuse is damaged, CHECK B+ and FPDM PWR circuits for short to ground before replacing.

KB9 CHECK FOR GROUND TO FPDM POWER SUPPLY RELAY

• Disconnect scan tool from DLC.
• Measure resistance of ground circuit between FPDM power supply relay harness connector and battery negative post.

Is resistance less than 5.0 ohms?
Yes No
GO to KB10 . REPAIR open circuit.

KB10 CHECK FOR OPEN FPDM PWR CIRCUIT

• Measure resistance of FPDM PWR circuit between FPDM power supply relay harness connector and FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
RECONNECT FPDM. GO to KB11 . The FPDM PWR circuit is open. GO to KB13 to help isolate fault.

KB11 CHECK VPWR CIRCUIT VOLTAGE (IGN START/RUN for Taurus/Sable) TO FPDM POWER SUPPLY RELAY

• Key on, engine off.
• Measure VPWR circuit voltage (IGN START/RUN for Taurus/Sable) at the FPDM power supply relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
REPLACE FPDM power supply relay. REPAIR open VPWR (or IGN START/RUN) circuit.

KB13 ISOLATE OPEN IN FPDM PWR CIRCUIT

• Disconnect IFS switch.
• Measure resistance of FPDM PWR circuit between IFS switch harness connector and FPDM power supply relay harness connector (for Escort and Mustang, CCRM harness connector [pin 5]).
• Measure resistance of FPDM PWR circuit between FPDM harness connector and IFS switch harness connector.

Are both resistances less than 5.0 ohms?
Yes No
VERIFY that the IFS switch is set (button depressed). If OK, REPLACE IFS switch. REPAIR open in appropriate area of FPDM PWR circuit.

KB15 CHECK FOR OPEN FPM CIRCUIT

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect FPDM.
• Disconnect PCM.
• Measure resistance of FPM circuit between PCM harness connector and the FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to KB16 . REPAIR open circuit.

KB16 CHECK FPM CIRCUIT FOR SHORT TO POWER IN HARNESS

• Key on, engine off.
• Measure voltage between FPM circuit at the PCM harness connector and ground.

Is voltage less than 1.0 volt?
Yes No
KEY OFF. GO to KB17 . REPAIR short circuit.

KB17 CHECK FPM CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect scan tool from DLC.
• Measure resistance between FPM circuit at the PCM harness connector and ground.

Is resistance greater than 10,000 ohms?
Yes No
GO to KB18 . REPAIR short circuit.

KB18 CHECK FOR FPM OUTPUT FROM FPDM

• Reconnect FPDM.
• Key on, engine off.
• Measure dc voltage between FPM circuit at the PCM harness connector and ground.

Is voltage between 0.02 and 1.0 volt dc? (It is OK for the voltage to cycle below this range and then return to within range.)
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPLACE FPDM.

KB25 CHECK CIRCUITS THAT MAY CAUSE AN INTERMITTENT LOSS OF POWER SUPPLY TO THE FPDM. ALSO CHECK FOR INTERMITTENT OPENS OR SHORTS ON THE FPM CIRCUIT.

• 
  Note: Be aware that P1233/1234 could be set if the inertia fuel shutoff (IFS) switch was tripped then reset.
  
• Key on, engine off.
• Access FPM PID.
  Note: With no fault detected, the FPDM will send a 50% duty cycle signal (all OK) to the PCM on the FPM circuit. Depending on scan tools, the FPM PID may display 50%, or a random value that is fluctuating between 85 and 115%.
  
  
• Observe FPM PID for an indication of a fault while completing the following (look for the FPM PID to change from the 50% value, or to stop fluctuating):
  • Shake, wiggle, bend the following circuits:
    • FPDM ground.
    • FPDM PWR circuit to FPDM.
    • For Escort and Mustang, the B+ circuit to CCRM pin 11. For Mustang, also the ground circuit to CCRM Pin 18.
    • For all except Escort and Mustang, the B+ and ground circuits to FPDM power supply relay.
    • FPM circuit between the FPDM and the PCM.
  • Lightly tap on the IFS Switch, FPDM and CCRM or FPDM power supply relay to simulate road shock.
• Key off.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. Unable to duplicate or identify fault at this time. GO to Z1 .

KB30 DTC P1235 OR P1236: IS DTC P1235 OR P1236 PRESENT IN KEY ON ENGINE OFF OR ENGINE RUNNING SELF TEST?

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
  Note: For LS6/LS8 and Thunderbird, the FPDM functions are incorporated in the Rear Electronics Module (REM). In the following steps, if directed to perform an action with the FPDM, complete the action with the REM. Refer to the pin numbers in the beginning of this pinpoint test.
  

Is DTC P1235 or P1236 present in Key On Engine Off or Engine Running Self-Test?
Yes No
A hard fault is present. GO to KB31 to check the FP circuit. DTC P1235 or P1236 is intermittent.

For LS6/LS8 and Thunderbird :

GO to KB42 .

All others :

GO to KB45 .

KB31 CHECK FOR OPEN FP CIRCUIT BETWEEN PCM AND FPDM

• Disconnect FPDM.
• Disconnect PCM.
• Measure resistance of FP circuit between PCM harness connector pin and the FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to KB32 . REPAIR open circuit.

KB32 CHECK FP CIRCUIT FOR SHORT TO POWER IN HARNESS

• Key on, engine off.
• Measure voltage between FP circuit at PCM harness connector pin and ground.

Is voltage less than 1.0 volt?
Yes No
KEY OFF. GO to KB33 . REPAIR short circuit.

KB33 CHECK FP CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect scan tool from DLC.
• Measure resistance between FP circuit at PCM harness connector pin and ground.

Is resistance greater than 10,000 ohms?
Yes No
For LS6/LS8 and Thunderbird :

GO to KB36 .

All others :

GO to KB34 . REPAIR short circuit.

KB34 CHECK FP CIRCUIT IN FPDM

• Reconnect FPDM.
• Key on, engine off.
• Measure voltage between FP circuit at PCM harness connector pin and ground.

Is voltage between 4.5 and 5.5 volts?
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPLACE FPDM.

KB36 CHECK FPF PID

• Key on, engine off.
• Access the FP and FPF PIDs on the scan tool (the FP PID may be used in the next step).
• While viewing the FPF PID for 20 seconds, check if the FPF PID will indicate YES. The FPF PID may read NO in the 20 seconds, but will change back to YES.

Does the FPF PID indicate YES within 20 seconds?
Yes No
GO to KB40 . GO to KB37 .

KB37 CHECK FP PID
Does the FP PID indicate between 70 and 80%?
Yes No
GO to KB38 . TURN KEY OFF then back ON. Wait 5 seconds. REPEAT test step. If result is now YES, follow YES result. If result is still NO, REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ).

KB38 ACCESS REM PIDS AND CHECK PWM_DC1 PID

• Access the PWM_DC1 PID from the REM menu (the PWM_DC1 PID indicates the signal sent to the REM from the PCM on the FP circuit).

Does the PWM_DC1 PID indicate between 70 and 80%?
Yes No
KEY OFF. No fault indicated. Disregard DTC P1235 or P1236. RETURN to Section 3 where DTC was received and proceed as directed. REPLACE REM.

KB40 CHECK REM CIRCUITRY VOLTAGE ON FP CIRCUIT AT PCM

• Key off.
• Disconnect PCM connector B (BODY).
• Key on, engine off.
• Measure voltage between pin B58 at PCM harness connector B and ground.

Is voltage greater than 8 volts?
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPLACE REM.

KB42 CHECK FP CIRCUIT FOR INTERMITTENT CONCERNS

• Key on, engine off.
• Access the REM PID access menu on the scan tool.
• Access the PWM_DC1 PID from the REM menu (the PWM_DC1 PID indicates the signal sent to the REM from the PCM on the FP circuit).
• Observe the PWM_DC1 PID for indication of a fault while completing the following (the PID value will change when a fault is detected):
  • Shake, wiggle and bend the FP circuit between the PCM (Pin B58) and REM (Pin J2-19).

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. GO to Z1 with the following data: PWM_DC1 PID (REM menu), FP PID (PCM menu, the FP PID is the signal the PCM is sending to the REM).

KB45 CHECK FP CIRCUIT FOR INTERMITTENT OPENS OR SHORTS

• Key on, engine off.
• Access FPM PID.
  Note: With no fault detected, the FPDM will send a 50% duty cycle signal (all OK) to the PCM on the FPM circuit. Depending on scan tools, the FPM PID may display 50%, or a random value that is fluctuating between 85 and 115%.
  
  
• Observe the FPM PID for an indication of a fault while completing the following (look for the FPM PID to change from the 50% value, or to stop fluctuating):
  • Shake, wiggle, bend the FP circuit between FPDM and the PCM.
  • Lightly tap on the FPDM (to simulate road shock).

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. GO to Z1 .

KB47 DTC P1237 OR P1238: IS DTC P1237 OR P1238 PRESENT IN KEY ON ENGINE OFF OR ENGINE RUNNING SELF TEST
Is DTC P1237 or P1238 present in Key On Engine Off or Key On Engine Running Self-Test?
Yes No
A hard fault is present. GO to KB48 . DTC P1237 or P1238 is possibly intermittent.

For LS6/LS8 and Thunderbird :

GO to KB67 .

All others :

GO to KB56 .

KB48 DOES THE ENGINE START?
Does the engine start?
Yes No
For LS6/LS8 and Thunderbird :

GO to KB80 .

All others :

DISCONNECT FPDM. GO to KB59 . For LS6/LS8 and Thunderbird :

GO to KB61 .

All others :

GO to KB49 to check fuel pump secondary circuits.

KB49 CHECK FP PWR, FP RTN AND INTERNAL FUEL PUMP CIRCUIT RESISTANCE

• Disconnect scan tool from DLC.
• Disconnect FPDM.
• Measure resistance between FP PWR circuit and the FP RTN circuit at the FPDM harness connector.

Is resistance less than 10.0 ohms?
Yes No
GO to KB50 . An open secondary circuit exists. GO to KB54 to isolate fault.

KB50 CHECK FP RTN CIRCUIT FOR SHORT TO POWER IN HARNESS

• Key on, engine off.
• Measure voltage between the FP RTN circuit in harness and chassis ground.

Is voltage less than 1.0 volt?
Yes No
GO to KB51 . REPAIR short circuit.

KB51 CHECK FP PWR CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect fuel pump.
• Measure resistance between the FP PWR circuit in harness and ground.

Is resistance greater than 10,000 ohms?
Yes No
GO to KB52 . REPAIR short circuit.

KB52 CHECK FOR VOLTAGE TO FUEL PUMP

• Reconnect FPDM.
• Reconnect scan tool.
• Key on, engine off.
• Access Output Test Mode on scan tool. (To complete this test step without a scan tool, the fuel pump can be commanded on for one second by cycling the key from off to on. Repeat as needed.)
• Connect digital multimeter between the FP PWR circuit and the FP RTN circuit at the fuel pump harness connector.
• While monitoring voltage, command outputs on (this commands the fuel pump on for about 5 seconds).

With the fuel pump commanded on, is the voltage greater than 10.0 volts?
Yes No
REPLACE fuel pump. VERIFY vehicle battery was at proper charge during test. VERIFY pump on command did not time-out before voltage check was made. If OK, REPLACE FPDM.

KB54 ISOLATE OPEN CIRCUIT

• Disconnect fuel pump.
• Measure resistance of the FP PWR circuit between the FPDM and fuel pump harness connectors.
• Measure resistance of the FP RTN circuit between the FPDM and fuel pump harness connectors.
• Measure internal resistance of the fuel pump.

Is each resistance less than 10.0 ohms?
Yes No
No fault is detected. VERIFY results of previous test steps. REPAIR open in appropriate circuit (if open was internal to pump, REPLACE fuel pump).

KB56 VERIFY THAT DTC P1237 OR P1238 IS INTERMITTENT

• 
  Note: When the FPDM is detecting a secondary fuel pump circuit fault (the wires going to the fuel pump), a 75% duty cycle signal will be sent to the PCM on the FPM circuit. On some scan tools, the FPM PID may display the 75% signal as a random value that is fluctuating between 250 and 400%.
  
• Key on, engine off.
• Access FPM PID.

Is the FPM PID 75% (or varying between 250 and 400%)?
Yes No
A hard fault is present. GO to KB48 . DTC P1237 or P1238 is intermittent. GO to KB57 .

KB57 CHECK FUEL PUMP SECONDARY CIRCUITS FOR INTERMITTENT OPEN OR SHORT

• Key on, engine off.
• Access FPM PID.
  Note: With no fault detected, the FPDM will send a 50% duty cycle signal (all OK) to the PCM on the FPM circuit. Depending on scan tools, the FPM PID may display 50%, or a random value that is fluctuating between 85 and 115%.
  
  
• Observe the FPM PID for an indication of a fault while completing the following (the FPM PID will change from the normal (all OK) reading when a fault is detected):
  • Shake, wiggle, bend the FP PWR circuit and FP RTN circuit between the FPDM and the fuel pump.
  • Lightly tap the fuel pump and the FPDM to simulate road shock.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. GO to KB58 .

KB58 CHECK FP PWR CIRCUIT FOR SHORT TO GROUND

• Disconnect FPDM.
• Connect a non-powered test lamp between the FP PWR circuit and the FPDM PWR circuit at the FPDM harness connector.
• Key on.
• Observe test lamp for an indication of a fault while completing the following (the test lamp will turn on when a fault is detected, indicating a short to ground):
  • Shake, wiggle, bend the FP PWR circuit between the FPDM and the fuel pump.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. RECONNECT FPDM. GO to Z1 .

KB59 CHECK FP PWR CIRCUIT FOR SHORT TO POWER

• FPDM disconnected.
• Key on, engine off.
• Measure voltage between the FP PWR circuit at the FPDM harness connector and chassis ground.

Is voltage less than 1.0 volt?
Yes No
GO to KB60 . REPAIR FP PWR circuit short to power.

KB60 CHECK FP RTN CIRCUIT FOR SHORT TO GROUND

• FPDM disconnected.
• Key on.
• Measure voltage between the FPDM PWR and FP RTN circuits at the FPDM harness connector.

Is voltage less than 1.0 volt?
Yes No
REPLACE FPDM. REPAIR FP RTN circuit short to ground.

KB61 CHECK REM/FP PWR AND GROUND CIRCUIT TO REM PINS J1-1, J1-2

• 
  Note: Verify inertia fuel shutoff (IFS) switch is not tripped.
  
• Disconnect REM connector J1.
• Key on.
• Measure voltage between pins J1-1 (REM/FP PWR) and J1-2 (GND) at the REM harness connector.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB49 (The FPDM functions are incorporated in the Rear Electronics Module (REM). In the following test steps, if directed to complete an action with the FPDM, complete the action with the REM. Refer to the pin numbers in the beginning of this pinpoint test). GO to KB62 .

KB62 CHECK REM/FP PWR CIRCUIT VOLTAGE TO REM USING CHASSIS GROUND AS A REFERENCE

• Key on.
• Measure voltage between pin J1-1 of the REM harness connector and chassis ground.

Is voltage greater than 10.5 volts?
Yes No
REPAIR open ground circuit in harness to pin J1-2 of the REM. KEY OFF. GO to KB63 .

KB63 CHECK FOR B+ TO FUEL PUMP RELAY HARNESS CONNECTOR

• Disconnect fuel pump relay.
• Measure B+ circuit voltage at fuel pump relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
GO to KB64 . VERIFY condition of related fuse(s). If OK, REPAIR open circuit. If B+ fuse is damaged, CHECK for B+ short to ground or FP RTN for short to power before replacing fuse.

KB64 CHECK FOR IGN START/RUN VOLTAGE (THROUGH IFS SWITCH) TO FUEL PUMP RELAY HARNESS CONNECTOR

• Disconnect REM connector J3.
• Key on.
• Measure IGN START/RUN circuit (from IFS switch) voltage at fuel pump relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB65 . VERIFY condition of related fuse. If fuse is damaged, CHECK for IGN START/RUN circuit short to ground before replacing fuse. If fuse is OK, GO to KB69 (to isolate open circuit).

KB65 CHECK GROUND CIRCUIT TO FUEL PUMP RELAY

• Measure resistance of ground circuit between the fuel pump relay harness connector and ground.

Is resistance less than 5.0 ohms?
Yes No
GO to KB66 . REPAIR open circuit.

KB66 CHECK REM/FP PWR CIRCUIT CONTINUITY

• Measure resistance of REM/FP PWR circuit between the fuel pump relay harness connector and the REM harness connector (pin J1-1).

Is resistance less than 5.0 ohms?
Yes No
REPLACE fuel pump relay. REPAIR open circuit.

KB67 CHECK REM/FP PWR, REM GROUND AND CIRCUITS ASSOCIATED WITH THE FUEL PUMP RELAY FOR INTERMITTENTS

• Disconnect REM connector J1.
• Connect a non-powered test lamp between pins J1-1 (REM/FP PWR) and J1-2 (GND) of the REM harness connector.
• Key on.
• Observe test lamp for an indication of a fault while completing the following (the test lamp will go out when a fault is detected):
  • Shake, wiggle and bend the REM/FP PWR and GND (pin J1-2) circuits to REM.
  • Shake, wiggle and bend the circuits going to the fuel pump relay (IGN START/RUN, B+ ground).
  • Lightly tap the fuel pump relay and IFS switch to simulate road shock.

Is a fault detected?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. GO to KB68 .

KB68 CHECK FP PWR AND FP RTN CIRCUITS FOR INTERMITTENT CONCERNS

• Connect a DVOM (set to measure resistance) between pins J1-11 (FP PWR) and J1-12 (FP RTN).
• Observe DVOM for an indication of a fault while completing the following (resistance will change suddenly [from less than 10 ohms] when a fault is detected):
  • Shake, wiggle and bend the FP PWR and FP RTN circuits between the fuel pump and REM.
• Connect DVOM between pin J1-12 (FP RTN) and ground.
• Observe DVOM for an indication of a fault while completing the following (resistance will change suddenly [from greater than 10,000 ohms] when a short to ground is detected):
  • Shake, wiggle and bend the FP PWR and FP RTN circuits between the fuel pump and REM.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. REMOVE DVOM, RECONNECT REM. GO to Z1 .

KB69 ISOLATE OPEN IN IGN START/RUN CIRCUIT

• Disconnect Inertia Fuel Shutoff (IFS) switch.
• Measure resistance across the normally closed contacts of the IFS switch. Note resistance.
• Measure resistance of IGN START/RUN circuit between the IFS switch and fuel pump relay harness connectors.

Are both resistances less than 5.0 ohms?
Yes No
REPAIR open IGN START/RUN circuit to IFS switch. If open was in IGN START/RUN circuit, REPAIR open. If open was in IFS switch, REPLACE switch.

KB70 SENT HERE FROM PINPOINT TEST HC WITH LOW VOLTAGE AT FUEL PUMP AND NO DTCs: CHECK BATTERY VOLTAGE WITH OUTPUTS COMMANDED ON

• 
  Note: For LS6/LS8 and Thunderbird, verify REM Self-Test has been previously performed.
  
• Scan tool connected.
• Fuel pump disconnected.
• Key on.
• Connect digital multimeter to the battery positive and battery negative posts.
• While monitoring battery voltage, command outputs on. Note voltage within 5 seconds.
• Command outputs off.

Was battery voltage greater than 11.0 volts?
Yes No
GO to KB71 . Battery voltage is low. REFER to Charging System, General Information Section 414-00 in the Workshop Manual.

KB71 CHECK GROUND CIRCUIT TO FUEL PUMP BY MEASURING VOLTAGE AT FUEL PUMP USING BATTERY NEGATIVE AS A REFERENCE

• Connect digital multimeter between the FP PWR circuit at the fuel pump harness connector and the battery negative post.
• Key on.
• While monitoring voltage, command outputs on. Note voltage within 5 seconds.

Is voltage greater than 10.5 volts?
Yes No
Ground fault to fuel pump indicated. CHECK all associated wiring and connections for the fuel pump and FPDM ground circuits. Carefully CHECK the FPDM ground connection to chassis ground. REPAIR as necessary. KEY OFF. Ground circuit to fuel pump is OK. GO to KB72 .

KB72 CHECK VOLTAGE TO FUEL PUMP DRIVER MODULE (FPDM)

• 
  Note: For LS6/LS8 and Thunderbird, the FPDM functions are incorporated in the Rear Electronics Module (REM). In the following steps, if directed to complete an action with the FPDM, complete the action with the REM.
  
• Disconnect fuel pump driver module (FPDM).
• Key on.
• Measure voltage between the FPDM PWR circuit at the FPDM harness connector and the battery negative post.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB73 . KEY OFF. Improper voltage is being supplied to FPDM. GO to KB75 .

KB73 CHECK FP PWR CIRCUIT

• Connect a jumper wire between the FPDM PWR pin and FP PWR pin at the FPDM harness connector.
• Key on.
• Measure voltage between the FP PWR circuit at the fuel pump harness connector and the battery negative post.

Is voltage greater than 10.5 volts, AND within 0.5 volt of the reading in KB72?

Yes No
KEY OFF. REMOVE jumper. VERIFY previous test steps. CHECK related connectors for corrosion, etc. If all checks are OK, REPLACE FPDM. KEY OFF. REMOVE jumper. CHECK for causes of high resistance in FP PWR circuit.

KB75 CHECK B+ TO FPDM POWER SUPPLY RELAY (or CCRM)

• Disconnect CCRM (Escort, Mustang) or FPDM power supply relay (all others).
• Key on (to put same load on battery as previous steps).
• For Escort, Mustang:
  • Measure voltage between pin 11 (B+) of the CCRM harness connector and the battery negative post.
• For all others:
  • Measure voltage between the B+ circuit at the FPDM power supply relay harness connector and the battery negative post.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB76 . Improper voltage is being supplied to the CCRM or FPDM power supply relay. CHECK associated wiring, connectors, etc. REPAIR as necessary.

KB76 CHECK FPDM PWR CIRCUIT

• For Escort, Mustang:
  • Connect a jumper wire between pin 11 (B+) and pin 5 at the CCRM harness connector.
• For all others:
  • Connect a jumper wire between the B+ and the FPDM PWR circuit at the FPDM power supply relay harness connector.
• Key on.
• Measure voltage between the FPDM PWR circuit at the FPDM harness connector and the battery negative post.

Is voltage greater than 10.5 volts?
Yes No
VERIFY previous test steps. CHECK related connectors for corrosion, etc. If all checks are OK, REPLACE FPDM. CHECK for causes of high resistance in associated connectors and wiring of the FPDM PWR VPWR circuit, including the IFS switch and its connector. REPAIR as necessary.

KB80 CHECK FP RTN CIRCUIT FOR SHORT TO GROUND

• Disconnect REM connector J1.
• Key on.
• Measure voltage between pins J1-1 and J1-12 at the REM harness connector.

Is voltage less than 1.0 volt?
Yes No
GO to KB67 . REPAIR FP RTN circuit short to ground.

KB85 COMPLETE REAR ELECTRONICS MODULE SELF-TEST TO VERIFY IFS SWITCH INPUT TO REM (REM PIN J3-8)

• Complete Rear Electronics Module Self-Test (refer to Workshop Manual section 419-10, Multifunction Electronic Control Modules, for directions).

Is REM DTC B2172 present?
Yes No
GO to KB86 . GO to A1 .

KB86 B2172: CHECK IFS SWITCH INPUT CIRCUIT TO REM (REM PIN J3-8)

• Disconnect REM connector J3.
• Key on, engine off.
• Measure voltage at pin J3-8 of the REM harness connector.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF.

If engine is a no start and REM DTC B2172 was received in on-demand self-test mode:

REPLACE REM.

If engine will start or REM DTC B2172 is a continuous memory DTC:

DTC is intermittent. If engine is a no start, return to Section 3 to continue diagnosis. If engine will start, GO to Z1 (even though PPT Z is designed for PCM intermittents, the diagnostic techniques will help with the REM diagnosis). KEY OFF. VERIFY IFS switch is not open. If OK, REPAIR open circuit between IFS switch and REM pin J3-8.

 

[hotcobra03]

po453.start at hx33.

you may have found issues,but was in manual tonite.

here is what that gives on codes.being a paste and copy it will give all of the pintests.just start at given step number.

po1237.start kb47


2003 PCED OBDII
SECTION 5: Pinpoint Tests


KB: Fuel Pump Driver Module (FPDM)

KB: Introduction


KB1 DTC P1233 OR P1234: IS DTC P1233 OR P1234 PRESENT IN KEY ON ENGINE OFF SELF TEST
Is DTC P1233 or P1234 present in Key On Engine Off Self-Test?
Yes No
A hard fault is present. GO to KB2 . The PCM is now receiving a signal from the FPDM. One possible cause of the DTC P1233 or P1234 is that the IFS switch was tripped, then reset.

If engine is now a no start:

Disregard the DTC P1233 or P1234 at this time. RETURN to Section 3 and CONTINUE as directed. After servicing the no start, to diagnose intermittent causes of the DTC P1233 or P1234, RETURN to GO to KB25 .

If engine will start:

GO to KB25 to diagnose intermittent condition.

KB2 DOES THE ENGINE START?
Does the engine start?
Yes No
GO to KB15 (to check the FPM circuit). VERIFY IFS switch is set (button depressed). If OK, GO to KB3 .

KB3 CHECK POWER AND GROUND CIRCUITS TO FPDM

• Disconnect FPDM.
• Key on, engine off.
• Measure voltage between the FPDM PWR pin and ground pin at the FPDM harness connector.

Is voltage greater than 10.5 volts?

Yes No
Key off. REPLACE FPDM. GO to KB4 .

KB4 CHECK POWER TO FPDM

• Key on, engine off.
• Measure voltage between the FPDM PWR pin at the FPDM harness connector and chassis ground.

Is voltage greater than 10.5 volts?

Yes No
REPAIR open ground circuit to FPDM. KEY OFF. No power to FPDM.

For Escort, Mustang:

GO to KB5 .

All Others:

GO to KB8 .

KB5 CHECK B+ VOLTAGE TO CCRM PIN 11 (FPDM POWER SUPPLY RELAY)

• Disconnect CCRM.
• Measure B+ circuit voltage at Pin 11 of the CCRM harness connector.

Is voltage greater than 10.5 volts?
Yes No
For Mustang:

GO to KB6 .

For Escort:

GO to KB7 . VERIFY integrity of related fuse. If OK, REPAIR open B+ circuit. If fuse is damaged, CHECK B+ and FPDM PWR circuits for short to ground before replacing.

KB6 CHECK GROUND CIRCUIT TO CCRM PIN 18

• Measure resistance of ground circuit between CCRM harness connector Pin 18 and chassis ground.

Is resistance less than 5.0 ohms?
Yes No
GO to KB7 . SERVICE open ground circuit.

KB7 CHECK FOR OPEN FPDM PWR CIRCUIT

• Measure resistance of FPDM PWR circuit between CCRM harness connector (pin 5) and FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
REPLACE CCRM. The FPDM PWR circuit is open. GO to KB13 to help isolate fault.

KB8 CHECK B+ VOLTAGE TO FPDM POWER SUPPLY RELAY

• Disconnect FPDM power supply relay.
• Measure B+ circuit voltage at the FPDM power supply relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
GO to KB9 . VERIFY integrity of related fuse. If OK, REPAIR open B+ circuit. If fuse is damaged, CHECK B+ and FPDM PWR circuits for short to ground before replacing.

KB9 CHECK FOR GROUND TO FPDM POWER SUPPLY RELAY

• Disconnect scan tool from DLC.
• Measure resistance of ground circuit between FPDM power supply relay harness connector and battery negative post.

Is resistance less than 5.0 ohms?
Yes No
GO to KB10 . REPAIR open circuit.

KB10 CHECK FOR OPEN FPDM PWR CIRCUIT

• Measure resistance of FPDM PWR circuit between FPDM power supply relay harness connector and FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
RECONNECT FPDM. GO to KB11 . The FPDM PWR circuit is open. GO to KB13 to help isolate fault.

KB11 CHECK VPWR CIRCUIT VOLTAGE (IGN START/RUN for Taurus/Sable) TO FPDM POWER SUPPLY RELAY

• Key on, engine off.
• Measure VPWR circuit voltage (IGN START/RUN for Taurus/Sable) at the FPDM power supply relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
REPLACE FPDM power supply relay. REPAIR open VPWR (or IGN START/RUN) circuit.

KB13 ISOLATE OPEN IN FPDM PWR CIRCUIT

• Disconnect IFS switch.
• Measure resistance of FPDM PWR circuit between IFS switch harness connector and FPDM power supply relay harness connector (for Escort and Mustang, CCRM harness connector [pin 5]).
• Measure resistance of FPDM PWR circuit between FPDM harness connector and IFS switch harness connector.

Are both resistances less than 5.0 ohms?
Yes No
VERIFY that the IFS switch is set (button depressed). If OK, REPLACE IFS switch. REPAIR open in appropriate area of FPDM PWR circuit.

KB15 CHECK FOR OPEN FPM CIRCUIT

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect FPDM.
• Disconnect PCM.
• Measure resistance of FPM circuit between PCM harness connector and the FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to KB16 . REPAIR open circuit.

KB16 CHECK FPM CIRCUIT FOR SHORT TO POWER IN HARNESS

• Key on, engine off.
• Measure voltage between FPM circuit at the PCM harness connector and ground.

Is voltage less than 1.0 volt?
Yes No
KEY OFF. GO to KB17 . REPAIR short circuit.

KB17 CHECK FPM CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect scan tool from DLC.
• Measure resistance between FPM circuit at the PCM harness connector and ground.

Is resistance greater than 10,000 ohms?
Yes No
GO to KB18 . REPAIR short circuit.

KB18 CHECK FOR FPM OUTPUT FROM FPDM

• Reconnect FPDM.
• Key on, engine off.
• Measure dc voltage between FPM circuit at the PCM harness connector and ground.

Is voltage between 0.02 and 1.0 volt dc? (It is OK for the voltage to cycle below this range and then return to within range.)
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPLACE FPDM.

KB25 CHECK CIRCUITS THAT MAY CAUSE AN INTERMITTENT LOSS OF POWER SUPPLY TO THE FPDM. ALSO CHECK FOR INTERMITTENT OPENS OR SHORTS ON THE FPM CIRCUIT.

• 
  Note: Be aware that P1233/1234 could be set if the inertia fuel shutoff (IFS) switch was tripped then reset.
  
• Key on, engine off.
• Access FPM PID.
  Note: With no fault detected, the FPDM will send a 50% duty cycle signal (all OK) to the PCM on the FPM circuit. Depending on scan tools, the FPM PID may display 50%, or a random value that is fluctuating between 85 and 115%.
  
  
• Observe FPM PID for an indication of a fault while completing the following (look for the FPM PID to change from the 50% value, or to stop fluctuating):
  • Shake, wiggle, bend the following circuits:
    • FPDM ground.
    • FPDM PWR circuit to FPDM.
    • For Escort and Mustang, the B+ circuit to CCRM pin 11. For Mustang, also the ground circuit to CCRM Pin 18.
    • For all except Escort and Mustang, the B+ and ground circuits to FPDM power supply relay.
    • FPM circuit between the FPDM and the PCM.
  • Lightly tap on the IFS Switch, FPDM and CCRM or FPDM power supply relay to simulate road shock.
• Key off.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. Unable to duplicate or identify fault at this time. GO to Z1 .

KB30 DTC P1235 OR P1236: IS DTC P1235 OR P1236 PRESENT IN KEY ON ENGINE OFF OR ENGINE RUNNING SELF TEST?

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
  Note: For LS6/LS8 and Thunderbird, the FPDM functions are incorporated in the Rear Electronics Module (REM). In the following steps, if directed to perform an action with the FPDM, complete the action with the REM. Refer to the pin numbers in the beginning of this pinpoint test.
  

Is DTC P1235 or P1236 present in Key On Engine Off or Engine Running Self-Test?
Yes No
A hard fault is present. GO to KB31 to check the FP circuit. DTC P1235 or P1236 is intermittent.

For LS6/LS8 and Thunderbird :

GO to KB42 .

All others :

GO to KB45 .

KB31 CHECK FOR OPEN FP CIRCUIT BETWEEN PCM AND FPDM

• Disconnect FPDM.
• Disconnect PCM.
• Measure resistance of FP circuit between PCM harness connector pin and the FPDM harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to KB32 . REPAIR open circuit.

KB32 CHECK FP CIRCUIT FOR SHORT TO POWER IN HARNESS

• Key on, engine off.
• Measure voltage between FP circuit at PCM harness connector pin and ground.

Is voltage less than 1.0 volt?
Yes No
KEY OFF. GO to KB33 . REPAIR short circuit.

KB33 CHECK FP CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect scan tool from DLC.
• Measure resistance between FP circuit at PCM harness connector pin and ground.

Is resistance greater than 10,000 ohms?
Yes No
For LS6/LS8 and Thunderbird :

GO to KB36 .

All others :

GO to KB34 . REPAIR short circuit.

KB34 CHECK FP CIRCUIT IN FPDM

• Reconnect FPDM.
• Key on, engine off.
• Measure voltage between FP circuit at PCM harness connector pin and ground.

Is voltage between 4.5 and 5.5 volts?
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPLACE FPDM.

KB36 CHECK FPF PID

• Key on, engine off.
• Access the FP and FPF PIDs on the scan tool (the FP PID may be used in the next step).
• While viewing the FPF PID for 20 seconds, check if the FPF PID will indicate YES. The FPF PID may read NO in the 20 seconds, but will change back to YES.

Does the FPF PID indicate YES within 20 seconds?
Yes No
GO to KB40 . GO to KB37 .

KB37 CHECK FP PID
Does the FP PID indicate between 70 and 80%?
Yes No
GO to KB38 . TURN KEY OFF then back ON. Wait 5 seconds. REPEAT test step. If result is now YES, follow YES result. If result is still NO, REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ).

KB38 ACCESS REM PIDS AND CHECK PWM_DC1 PID

• Access the PWM_DC1 PID from the REM menu (the PWM_DC1 PID indicates the signal sent to the REM from the PCM on the FP circuit).

Does the PWM_DC1 PID indicate between 70 and 80%?
Yes No
KEY OFF. No fault indicated. Disregard DTC P1235 or P1236. RETURN to Section 3 where DTC was received and proceed as directed. REPLACE REM.

KB40 CHECK REM CIRCUITRY VOLTAGE ON FP CIRCUIT AT PCM

• Key off.
• Disconnect PCM connector B (BODY).
• Key on, engine off.
• Measure voltage between pin B58 at PCM harness connector B and ground.

Is voltage greater than 8 volts?
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPLACE REM.

KB42 CHECK FP CIRCUIT FOR INTERMITTENT CONCERNS

• Key on, engine off.
• Access the REM PID access menu on the scan tool.
• Access the PWM_DC1 PID from the REM menu (the PWM_DC1 PID indicates the signal sent to the REM from the PCM on the FP circuit).
• Observe the PWM_DC1 PID for indication of a fault while completing the following (the PID value will change when a fault is detected):
  • Shake, wiggle and bend the FP circuit between the PCM (Pin B58) and REM (Pin J2-19).

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. GO to Z1 with the following data: PWM_DC1 PID (REM menu), FP PID (PCM menu, the FP PID is the signal the PCM is sending to the REM).

KB45 CHECK FP CIRCUIT FOR INTERMITTENT OPENS OR SHORTS

• Key on, engine off.
• Access FPM PID.
  Note: With no fault detected, the FPDM will send a 50% duty cycle signal (all OK) to the PCM on the FPM circuit. Depending on scan tools, the FPM PID may display 50%, or a random value that is fluctuating between 85 and 115%.
  
  
• Observe the FPM PID for an indication of a fault while completing the following (look for the FPM PID to change from the 50% value, or to stop fluctuating):
  • Shake, wiggle, bend the FP circuit between FPDM and the PCM.
  • Lightly tap on the FPDM (to simulate road shock).

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. GO to Z1 .

KB47 DTC P1237 OR P1238: IS DTC P1237 OR P1238 PRESENT IN KEY ON ENGINE OFF OR ENGINE RUNNING SELF TEST
Is DTC P1237 or P1238 present in Key On Engine Off or Key On Engine Running Self-Test?
Yes No
A hard fault is present. GO to KB48 . DTC P1237 or P1238 is possibly intermittent.

For LS6/LS8 and Thunderbird :

GO to KB67 .

All others :

GO to KB56 .

KB48 DOES THE ENGINE START?
Does the engine start?
Yes No
For LS6/LS8 and Thunderbird :

GO to KB80 .

All others :

DISCONNECT FPDM. GO to KB59 . For LS6/LS8 and Thunderbird :

GO to KB61 .

All others :

GO to KB49 to check fuel pump secondary circuits.

KB49 CHECK FP PWR, FP RTN AND INTERNAL FUEL PUMP CIRCUIT RESISTANCE

• Disconnect scan tool from DLC.
• Disconnect FPDM.
• Measure resistance between FP PWR circuit and the FP RTN circuit at the FPDM harness connector.

Is resistance less than 10.0 ohms?
Yes No
GO to KB50 . An open secondary circuit exists. GO to KB54 to isolate fault.

KB50 CHECK FP RTN CIRCUIT FOR SHORT TO POWER IN HARNESS

• Key on, engine off.
• Measure voltage between the FP RTN circuit in harness and chassis ground.

Is voltage less than 1.0 volt?
Yes No
GO to KB51 . REPAIR short circuit.

KB51 CHECK FP PWR CIRCUIT FOR SHORT TO GROUND IN HARNESS

• Disconnect fuel pump.
• Measure resistance between the FP PWR circuit in harness and ground.

Is resistance greater than 10,000 ohms?
Yes No
GO to KB52 . REPAIR short circuit.

KB52 CHECK FOR VOLTAGE TO FUEL PUMP

• Reconnect FPDM.
• Reconnect scan tool.
• Key on, engine off.
• Access Output Test Mode on scan tool. (To complete this test step without a scan tool, the fuel pump can be commanded on for one second by cycling the key from off to on. Repeat as needed.)
• Connect digital multimeter between the FP PWR circuit and the FP RTN circuit at the fuel pump harness connector.
• While monitoring voltage, command outputs on (this commands the fuel pump on for about 5 seconds).

With the fuel pump commanded on, is the voltage greater than 10.0 volts?
Yes No
REPLACE fuel pump. VERIFY vehicle battery was at proper charge during test. VERIFY pump on command did not time-out before voltage check was made. If OK, REPLACE FPDM.

KB54 ISOLATE OPEN CIRCUIT

• Disconnect fuel pump.
• Measure resistance of the FP PWR circuit between the FPDM and fuel pump harness connectors.
• Measure resistance of the FP RTN circuit between the FPDM and fuel pump harness connectors.
• Measure internal resistance of the fuel pump.

Is each resistance less than 10.0 ohms?
Yes No
No fault is detected. VERIFY results of previous test steps. REPAIR open in appropriate circuit (if open was internal to pump, REPLACE fuel pump).

KB56 VERIFY THAT DTC P1237 OR P1238 IS INTERMITTENT

• 
  Note: When the FPDM is detecting a secondary fuel pump circuit fault (the wires going to the fuel pump), a 75% duty cycle signal will be sent to the PCM on the FPM circuit. On some scan tools, the FPM PID may display the 75% signal as a random value that is fluctuating between 250 and 400%.
  
• Key on, engine off.
• Access FPM PID.

Is the FPM PID 75% (or varying between 250 and 400%)?
Yes No
A hard fault is present. GO to KB48 . DTC P1237 or P1238 is intermittent. GO to KB57 .

KB57 CHECK FUEL PUMP SECONDARY CIRCUITS FOR INTERMITTENT OPEN OR SHORT

• Key on, engine off.
• Access FPM PID.
  Note: With no fault detected, the FPDM will send a 50% duty cycle signal (all OK) to the PCM on the FPM circuit. Depending on scan tools, the FPM PID may display 50%, or a random value that is fluctuating between 85 and 115%.
  
  
• Observe the FPM PID for an indication of a fault while completing the following (the FPM PID will change from the normal (all OK) reading when a fault is detected):
  • Shake, wiggle, bend the FP PWR circuit and FP RTN circuit between the FPDM and the fuel pump.
  • Lightly tap the fuel pump and the FPDM to simulate road shock.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. GO to KB58 .

KB58 CHECK FP PWR CIRCUIT FOR SHORT TO GROUND

• Disconnect FPDM.
• Connect a non-powered test lamp between the FP PWR circuit and the FPDM PWR circuit at the FPDM harness connector.
• Key on.
• Observe test lamp for an indication of a fault while completing the following (the test lamp will turn on when a fault is detected, indicating a short to ground):
  • Shake, wiggle, bend the FP PWR circuit between the FPDM and the fuel pump.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. RECONNECT FPDM. GO to Z1 .

KB59 CHECK FP PWR CIRCUIT FOR SHORT TO POWER

• FPDM disconnected.
• Key on, engine off.
• Measure voltage between the FP PWR circuit at the FPDM harness connector and chassis ground.

Is voltage less than 1.0 volt?
Yes No
GO to KB60 . REPAIR FP PWR circuit short to power.

KB60 CHECK FP RTN CIRCUIT FOR SHORT TO GROUND

• FPDM disconnected.
• Key on.
• Measure voltage between the FPDM PWR and FP RTN circuits at the FPDM harness connector.

Is voltage less than 1.0 volt?
Yes No
REPLACE FPDM. REPAIR FP RTN circuit short to ground.

KB61 CHECK REM/FP PWR AND GROUND CIRCUIT TO REM PINS J1-1, J1-2

• 
  Note: Verify inertia fuel shutoff (IFS) switch is not tripped.
  
• Disconnect REM connector J1.
• Key on.
• Measure voltage between pins J1-1 (REM/FP PWR) and J1-2 (GND) at the REM harness connector.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB49 (The FPDM functions are incorporated in the Rear Electronics Module (REM). In the following test steps, if directed to complete an action with the FPDM, complete the action with the REM. Refer to the pin numbers in the beginning of this pinpoint test). GO to KB62 .

KB62 CHECK REM/FP PWR CIRCUIT VOLTAGE TO REM USING CHASSIS GROUND AS A REFERENCE

• Key on.
• Measure voltage between pin J1-1 of the REM harness connector and chassis ground.

Is voltage greater than 10.5 volts?
Yes No
REPAIR open ground circuit in harness to pin J1-2 of the REM. KEY OFF. GO to KB63 .

KB63 CHECK FOR B+ TO FUEL PUMP RELAY HARNESS CONNECTOR

• Disconnect fuel pump relay.
• Measure B+ circuit voltage at fuel pump relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
GO to KB64 . VERIFY condition of related fuse(s). If OK, REPAIR open circuit. If B+ fuse is damaged, CHECK for B+ short to ground or FP RTN for short to power before replacing fuse.

KB64 CHECK FOR IGN START/RUN VOLTAGE (THROUGH IFS SWITCH) TO FUEL PUMP RELAY HARNESS CONNECTOR

• Disconnect REM connector J3.
• Key on.
• Measure IGN START/RUN circuit (from IFS switch) voltage at fuel pump relay harness connector.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB65 . VERIFY condition of related fuse. If fuse is damaged, CHECK for IGN START/RUN circuit short to ground before replacing fuse. If fuse is OK, GO to KB69 (to isolate open circuit).

KB65 CHECK GROUND CIRCUIT TO FUEL PUMP RELAY

• Measure resistance of ground circuit between the fuel pump relay harness connector and ground.

Is resistance less than 5.0 ohms?
Yes No
GO to KB66 . REPAIR open circuit.

KB66 CHECK REM/FP PWR CIRCUIT CONTINUITY

• Measure resistance of REM/FP PWR circuit between the fuel pump relay harness connector and the REM harness connector (pin J1-1).

Is resistance less than 5.0 ohms?
Yes No
REPLACE fuel pump relay. REPAIR open circuit.

KB67 CHECK REM/FP PWR, REM GROUND AND CIRCUITS ASSOCIATED WITH THE FUEL PUMP RELAY FOR INTERMITTENTS

• Disconnect REM connector J1.
• Connect a non-powered test lamp between pins J1-1 (REM/FP PWR) and J1-2 (GND) of the REM harness connector.
• Key on.
• Observe test lamp for an indication of a fault while completing the following (the test lamp will go out when a fault is detected):
  • Shake, wiggle and bend the REM/FP PWR and GND (pin J1-2) circuits to REM.
  • Shake, wiggle and bend the circuits going to the fuel pump relay (IGN START/RUN, B+ ground).
  • Lightly tap the fuel pump relay and IFS switch to simulate road shock.

Is a fault detected?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. GO to KB68 .

KB68 CHECK FP PWR AND FP RTN CIRCUITS FOR INTERMITTENT CONCERNS

• Connect a DVOM (set to measure resistance) between pins J1-11 (FP PWR) and J1-12 (FP RTN).
• Observe DVOM for an indication of a fault while completing the following (resistance will change suddenly [from less than 10 ohms] when a fault is detected):
  • Shake, wiggle and bend the FP PWR and FP RTN circuits between the fuel pump and REM.
• Connect DVOM between pin J1-12 (FP RTN) and ground.
• Observe DVOM for an indication of a fault while completing the following (resistance will change suddenly [from greater than 10,000 ohms] when a short to ground is detected):
  • Shake, wiggle and bend the FP PWR and FP RTN circuits between the fuel pump and REM.

Is a fault indicated?
Yes No
ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. REMOVE DVOM, RECONNECT REM. GO to Z1 .

KB69 ISOLATE OPEN IN IGN START/RUN CIRCUIT

• Disconnect Inertia Fuel Shutoff (IFS) switch.
• Measure resistance across the normally closed contacts of the IFS switch. Note resistance.
• Measure resistance of IGN START/RUN circuit between the IFS switch and fuel pump relay harness connectors.

Are both resistances less than 5.0 ohms?
Yes No
REPAIR open IGN START/RUN circuit to IFS switch. If open was in IGN START/RUN circuit, REPAIR open. If open was in IFS switch, REPLACE switch.

KB70 SENT HERE FROM PINPOINT TEST HC WITH LOW VOLTAGE AT FUEL PUMP AND NO DTCs: CHECK BATTERY VOLTAGE WITH OUTPUTS COMMANDED ON

• 
  Note: For LS6/LS8 and Thunderbird, verify REM Self-Test has been previously performed.
  
• Scan tool connected.
• Fuel pump disconnected.
• Key on.
• Connect digital multimeter to the battery positive and battery negative posts.
• While monitoring battery voltage, command outputs on. Note voltage within 5 seconds.
• Command outputs off.

Was battery voltage greater than 11.0 volts?
Yes No
GO to KB71 . Battery voltage is low. REFER to Charging System, General Information Section 414-00 in the Workshop Manual.

KB71 CHECK GROUND CIRCUIT TO FUEL PUMP BY MEASURING VOLTAGE AT FUEL PUMP USING BATTERY NEGATIVE AS A REFERENCE

• Connect digital multimeter between the FP PWR circuit at the fuel pump harness connector and the battery negative post.
• Key on.
• While monitoring voltage, command outputs on. Note voltage within 5 seconds.

Is voltage greater than 10.5 volts?
Yes No
Ground fault to fuel pump indicated. CHECK all associated wiring and connections for the fuel pump and FPDM ground circuits. Carefully CHECK the FPDM ground connection to chassis ground. REPAIR as necessary. KEY OFF. Ground circuit to fuel pump is OK. GO to KB72 .

KB72 CHECK VOLTAGE TO FUEL PUMP DRIVER MODULE (FPDM)

• 
  Note: For LS6/LS8 and Thunderbird, the FPDM functions are incorporated in the Rear Electronics Module (REM). In the following steps, if directed to complete an action with the FPDM, complete the action with the REM.
  
• Disconnect fuel pump driver module (FPDM).
• Key on.
• Measure voltage between the FPDM PWR circuit at the FPDM harness connector and the battery negative post.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB73 . KEY OFF. Improper voltage is being supplied to FPDM. GO to KB75 .

KB73 CHECK FP PWR CIRCUIT

• Connect a jumper wire between the FPDM PWR pin and FP PWR pin at the FPDM harness connector.
• Key on.
• Measure voltage between the FP PWR circuit at the fuel pump harness connector and the battery negative post.

Is voltage greater than 10.5 volts, AND within 0.5 volt of the reading in KB72?

Yes No
KEY OFF. REMOVE jumper. VERIFY previous test steps. CHECK related connectors for corrosion, etc. If all checks are OK, REPLACE FPDM. KEY OFF. REMOVE jumper. CHECK for causes of high resistance in FP PWR circuit.

KB75 CHECK B+ TO FPDM POWER SUPPLY RELAY (or CCRM)

• Disconnect CCRM (Escort, Mustang) or FPDM power supply relay (all others).
• Key on (to put same load on battery as previous steps).
• For Escort, Mustang:
  • Measure voltage between pin 11 (B+) of the CCRM harness connector and the battery negative post.
• For all others:
  • Measure voltage between the B+ circuit at the FPDM power supply relay harness connector and the battery negative post.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to KB76 . Improper voltage is being supplied to the CCRM or FPDM power supply relay. CHECK associated wiring, connectors, etc. REPAIR as necessary.

KB76 CHECK FPDM PWR CIRCUIT

• For Escort, Mustang:
  • Connect a jumper wire between pin 11 (B+) and pin 5 at the CCRM harness connector.
• For all others:
  • Connect a jumper wire between the B+ and the FPDM PWR circuit at the FPDM power supply relay harness connector.
• Key on.
• Measure voltage between the FPDM PWR circuit at the FPDM harness connector and the battery negative post.

Is voltage greater than 10.5 volts?
Yes No
VERIFY previous test steps. CHECK related connectors for corrosion, etc. If all checks are OK, REPLACE FPDM. CHECK for causes of high resistance in associated connectors and wiring of the FPDM PWR VPWR circuit, including the IFS switch and its connector. REPAIR as necessary.

KB80 CHECK FP RTN CIRCUIT FOR SHORT TO GROUND

• Disconnect REM connector J1.
• Key on.
• Measure voltage between pins J1-1 and J1-12 at the REM harness connector.

Is voltage less than 1.0 volt?
Yes No
GO to KB67 . REPAIR FP RTN circuit short to ground.

KB85 COMPLETE REAR ELECTRONICS MODULE SELF-TEST TO VERIFY IFS SWITCH INPUT TO REM (REM PIN J3-8)

• Complete Rear Electronics Module Self-Test (refer to Workshop Manual section 419-10, Multifunction Electronic Control Modules, for directions).

Is REM DTC B2172 present?
Yes No
GO to KB86 . GO to A1 .

KB86 B2172: CHECK IFS SWITCH INPUT CIRCUIT TO REM (REM PIN J3-8)

• Disconnect REM connector J3.
• Key on, engine off.
• Measure voltage at pin J3-8 of the REM harness connector.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF.

If engine is a no start and REM DTC B2172 was received in on-demand self-test mode:

REPLACE REM.

If engine will start or REM DTC B2172 is a continuous memory DTC:

DTC is intermittent. If engine is a no start, return to Section 3 to continue diagnosis. If engine will start, GO to Z1 (even though PPT Z is designed for PCM intermittents, the diagnostic techniques will help with the REM diagnosis). KEY OFF. VERIFY IFS switch is not open. If OK, REPAIR open circuit between IFS switch and REM pin J3-8.

 

[hotcobra03]

po453,start hx33




2003 PCED OBDII
SECTION 5: Pinpoint Tests
HX: Evaporative Emission (EVAP) Monitor and System

HX: Introduction
HX1 DTC P0443: INSPECT EVAP CANISTER PURGE VALVE CIRCUIT FOR INTERMITTENT FAILURE

• Rerun KOEO, KOER Self-Tests and retrieve Continuous Memory DTCs.

Is DTC P0443 present in Continuous Memory Self-Test only?
Yes No
The fault that produced Continuous Memory DTC P0443 can be intermittent. GO to Z1 . If OK REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). GO to HX2 .

HX2 DTC P0443: CHECK VPWR VOLTAGE TO EVAP CANISTER PURGE VALVE

• Key off.
• Disconnect EVAP canister purge valve.
• Key on, engine off.
• Measure voltage between VPWR circuit at the EVAP canister purge valve harness connector and battery negative post.

Is voltage greater than 10.5 volts?
Yes No
For LS6/LS8/Thunderbird/2.3L Focus:

KEY OFF. GO to HX3 .

For All others:

KEY OFF. GO to HX4 REPAIR open circuit.

HX3 CHECK EVAP CANISTER PURGE VALVE RESISTANCE FOR LS6/LS8/THUNDERBIRD/2.3L FOCUS

• 
  Note: EVAP canister purge valve resistance reading must be taken with engine cooled down.
  
• Disconnect EVAP canister purge valve.
• Measure EVAP canister purge valve resistance.

Is resistance between 2.5 and 6.0 ohms?
Yes No
GO to HX5 . REPLACE damaged EVAP canister purge valve. COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ).

HX4 CHECK EVAP CANISTER PURGE VALVE RESISTANCE

• 
  Note: EVAP canister purge valve resistance reading must be taken with engine cooled down.
  
• Disconnect EVAP canister purge valve.
• Measure EVAP canister purge valve resistance.

Is resistance between 30 and 38 ohms?
Yes No
GO to HX5 . REPLACE damaged EVAP canister purge valve. COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ).

HX5 CHECK EVAP CANISTER PURGE VALVE CIRCUIT FOR OPEN IN HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Measure resistance of EVAP canister purge valve circuit between PCM harness connector pin and EVAP canister purge valve harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to HX6 . REPAIR open circuit.

HX6 CHECK EVAP CANISTER PURGE VALVE CIRCUIT FOR SHORT TO PWR GND IN HARNESS

• Disconnect scan tool from DLC.
• Measure resistance between EVAP canister purge valve circuit at the EVAP canister purge valve harness connector and battery negative post.

Is resistance greater than 10,000 ohms?
Yes No
GO to HX7 . REPAIR short circuit.

HX7 CHECK EVAP CANISTER PURGE VALVE CIRCUIT FOR SHORT TO VPWR IN HARNESS

• Key on, engine off.
• Measure voltage between EVAP canister purge valve circuit at the EVAP canister purge valve harness connector and battery negative post.

Is voltage greater than 10.5 volts?
Yes No
REPAIR short circuit. REPLACE PCM. (Refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ).

HX18 DTC P1450: CHECK FOR VISUAL CAUSES OF EXCESSIVE FUEL TANK VACUUM

• 
  Note: If the EVAP canister-CV solenoid and fuel tank assemblies are not accessible during this pinpoint test step, GO to Evaporative Emissions, Section 303 in the Workshop Manual for removal instructions. For Aviator application, REFER to Section 310 in the Workshop Manual for removal instructions.
  
• Check for kinks or bends in the fuel vapor hoses/tubes (EVAP canister purge outlet tube and EVAP canister tube).
• Visually inspect EVAP canister inlet port, CV solenoid filter and canister vent hose assembly for contamination or debris.
• Check CV solenoid filter for blockage or contamination.

Is a fault indicated?
Yes No
REMOVE any contamination or debris around fuel vapor hoses/tubes and EVAP canister- CV solenoid assembly. REMOVE kinks or bends in EVAP canister purge outlet tube, EVAP canister tube and canister vent hose assembly. CLEAR Continuous Memory DTCs. FOLLOW the Vehicle Preparation for Monitor Repair Verification Drive Cycle and COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Drive Cycles ). RETRIEVE Continuous Memory DTCs. If DTC 1450 is still present, GO to HX19 . GO to HX19 .

HX19 CHECK FUEL TANK PRESSURE SENSOR VOLTAGE

• Connect scan tool.
• Key on, engine off.
• Access FTP V PID.

Is the FTP V PID between 2.40 to 2.80 volts with the fuel filler cap on?
Yes No
A possible intermittent condition on the FTP sensor circuit can cause the DTC P1450. GO to Z1 . If circuit is OK, REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310), Diagnostic Trouble Code/Symptom Chart in the Workshop Manual for a blocked (plugged) EVAP system condition. KEY OFF. GO to HX20 .

HX20 CHECK FUEL TANK PRESSURE SENSOR VOLTAGE WITH FUEL FILLER CAP REMOVED

• Remove the fuel filler cap.
• Key on, engine off.
• Access FTP V PID.

Is the FTP V PID between 2.40 to 2.80 volts with fuel filler cap off?
Yes No
REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310), in the Workshop Manual for a blocked (plugged) EVAP system condition. KEY OFF. GO to HX21 .

HX21 CHECK FOR OTHER DTCS PRESENT

• Check for other three wire sensor DTCs (KOEO, KOER or Continuous Memory) present with the DTC P1450.

Are other DTCs present?
Yes No
RETURN to Diagnostic Subroutines, Section 4 , for direction in addressing the other DTCs. KEY OFF. GO to HX22 .

HX22 CHECK VREF FROM PCM TO FTP SENSOR

• Disconnect FTP sensor.
• Key on, engine off.
• Measure voltage between VREF and SIG RTN circuits at the FTP sensor harness connector.

Is voltage between 4.0 and 6.0 volts?
Yes No
KEY OFF. REPLACE damaged FTP sensor. CLEAR Continuous Memory DTCs. FOLLOW the Vehicle Preparation for Monitor Repair Verification Drive Cycle and COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ). RETRIEVE Continuous Memory DTCs. If DTC P1450 is still present, REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310), Diagnostic Trouble Code/Symptom Chart, in the Workshop Manual. KEY OFF. GO to HX23 .

HX23 CHECK FOR OPEN VREF AND SIG RTN CIRCUITS BETWEEN PCM AND FTP SENSOR

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Measure resistance of VREF circuit between PCM harness connector pin and FTP sensor harness connector.
• Measure resistance of SIG RTN circuit between PCM harness connector pin and FTP sensor harness connector.

Is each resistance less than 5.0 ohms?
Yes No
REPLACE PCM (REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPAIR open circuit.

HX26 DTC P0452: CHECK FOR FTP SENSOR CONNECTOR CONTAMINATION

• Key off.
• Visually check for liquid fuel contamination of the FTP sensor electrical connector.
• Check for completely submerged FTP sensor (tank mounted type only) in liquid fuel (can affect correct FTP voltage reading).

Does FTP sensor and its electrical connector show signs of fuel contamination?
Yes No
REPAIR FTP sensor electrical connector as necessary. ADJUST fuel tank overfill. GO to HX27 .

HX27 CHECK FOR LOW FTP SENSOR VOLTAGE

• 
  Note: FTP sensor input with no pressure/vacuum on the fuel tank (filler cap open or not open to atmosphere) is between 2.37 and 2.97 volts.
  
• Connect scan tool.
• Key on, engine off.
• Access FTP V PID.
• If FTP V PID is not present on the scan tool, measure voltage between FTP and SIG RTN circuits at the PCM harness connector with PCM connected.

Is measured voltage or FTP V PID reading less than 0.22 volt?
Yes No
KEY OFF. GO to HX28 . The fault that produced the DTC P0452 is intermittent. GO to Z1 .

HX28 CHECK OPPOSITE INDUCED HIGH FTP SIGNAL

• Disconnect FTP sensor.
• Connect a jumper wire between VREF circuit and FTP circuits at the FTP sensor harness connector.
• Key on, engine off.
• Measure voltage between FTP circuit at the FTP sensor harness connector and chassis ground.

Is measured voltage reading between 4.0 and 6.0 volts?
Yes No
REPLACE FTP sensor. REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310) in the Workshop Manual for component removal and installation. RESTORE vehicle. FOLLOW the Vehicle Preparation for Monitor Repair Verification Drive Cycle and COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ). REMOVE jumper. GO to HX29 .

HX29 CHECK VOLTAGE BETWEEN VREF AND SIG RTN CIRCUITS AT FTP SENSOR

• Key on, engine off.
• Measure voltage between VREF and SIG RTN circuits at the FTP sensor harness connector.

Is voltage between 4.0 and 6.0 volts?
Yes No
KEY OFF. GO to HX30 . VREF voltage is out of range. GO to C1 .

HX30 CHECK FTP CIRCUIT FOR SHORT TO SIG RTN OR PWR GND IN HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Disconnect scan tool from DLC.
• Measure resistance between FTP and SIG RTN circuits at the PCM harness connector.
• Measure resistance between FTP circuit at the PCM harness connector and battery negative post.

Is each resistance greater than 10,000 ohms?
Yes No
REPLACE PCM (REFER to Section 2, Drive Cycles ). REPAIR short circuit.

HX33 DTC P0453: CHECK FOR HIGH FTP SENSOR VOLTAGE

• 
  Note: FTP sensor input with no pressure/vacuum on the fuel tank (fuel filler cap open or not open to atmosphere) is 2.37 to 2.97 volts.
  
• Connect scan tool.
• Key on, engine off.
• Access FTP V PID.
• If FTP V PID is not present on the scan tool, measure voltage between FTP and SIG RTN circuits at the PCM harness connector with PCM connected.

Is measured voltage or FTP V PID reading greater than 4.50 volts?
Yes No
KEY OFF. GO to HX34 . The fault that produced DTC P0453 is intermittent. GO to Z1 .

HX34 CHECK FTP CIRCUIT FOR SHORT TO POWER

• Disconnect FTP sensor.
• Key on, engine off.
• Measure voltage between FTP circuit at the FTP sensor harness connector and battery negative post.

Is the voltage greater than 10.5 volts?
Yes No
KEY OFF. The FTP is indicating a short to VPWR. GO to HX35 . KEY OFF. GO to HX36 .

HX35 CHECK FTP CIRCUIT FOR SHORT TO VPWR IN HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Key on, engine off.
• Measure the voltage between FTP circuit at the PCM harness connector and battery negative post.

Is voltage greater than 10.5 volts?
Yes No
REPAIR short circuit. REPLACE PCM. (REFER to Section 2 , Flash EEPROM.)

HX36 CHECK OPPOSITE INDUCED LOW FTP SIGNAL

• Connect a jumper wire between SIG RTN and FTP circuits at the FTP sensor harness connector.
• Key on, engine off.
• If a scan tool communication concern exists, turn the key off, remove jumper immediately and GO to HX41 .
• Access FTP V PID.
• If FTP V PID is not present on the scan tool, measure voltage between FTP and SIG RTN circuits at the PCM harness connector with PCM connected.

Is measured voltage or FTP V PID reading less than 0.10 volt?
Yes No
REMOVE jumper. GO to HX37 . Unable to induce opposite signal. KEY OFF. GO to HX39 .

HX37 CHECK FOR IN RANGE VOLTAGE BETWEEN VREF AND SIG RTN CIRCUITS AT FTP SENSOR

• Key on, engine off.
• Measure voltage between VREF and SIG RTN circuits at the FTP sensor vehicle harness connector.

Is voltage between 4.0 and 6.0 volts?
Yes No
KEY OFF. GO to HX38 . VREF voltage is out of range. GO to C1 .

HX38 CHECK FTP CIRCUIT FOR SHORT TO VREF IN SENSOR OR HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Measure resistance between FTP and VREF circuits at the PCM harness connector. (For 150 PIN PCM, measure to both VREF pins.)

Is the resistance greater than 10,000 ohms?
Yes No
REPLACE FTP sensor. REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310), in the Workshop Manual for component removal and installation. RESTORE vehicle. FOLLOW the Vehicle Preparation for Monitor Repair Verification Drive Cycle and COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ). REPAIR short circuit.

HX39 CHECK FTP CIRCUIT FOR OPEN IN HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Measure resistance of FTP circuit between PCM harness connector pin and FTP sensor harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to HX40 . REPAIR open circuit.

HX40 CHECK FOR OPEN SIG RTN CIRCUIT BETWEEN PCM AND FTP SENSOR

• Measure resistance of SIG RTN circuit between PCM harness connector pin and FTP sensor harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to HX41 . REPAIR open circuit.

HX41 CHECK FTP CIRCUIT FOR SHORT TO VREF IN PCM

• PCM disconnected.
• Measure resistance between FTP and VREF circuits at the PCM harness connector. (For 150 PIN PCM, measure to both VREF pins.)

Is the resistance greater than 10,000 ohms?
Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPAIR short circuit.

HX43 DTC P0457: CHECK FOR MISSING OR LEAKING FUEL FILLER CAP

• Check for missing fuel filler cap.
• Check for a loose fuel filler cap.
• Check for possible cross-thread fuel filler cap condition.

Is a concern present with the proper installation of the fuel filler cap?
Yes No
REPLACE cross-threaded or damaged fuel filler cap. RECONNECT and TIGHTEN the fuel filler cap only one-eighth turn so that the cap initially clicks by sound or touch. COMPLETE PCM KAM Reset to clear DTCs and adaptive memory. (REFER to Section 2, Diagnostic Methods ). COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ). RERUN Quick Test. If DTC P0455 is present, REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310), Diagnostic Trouble Code/Symptom Chart in the Workshop Manual. COMPLETE PCM KAM Reset to clear DTCs and adaptive memory. (REFER to Section 2, Diagnostic Methods ). COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ). RERUN Quick Test. If DTC P0455 is present, REFER to Evaporative Emissions, Section 303 (for Aviator, REFER to Section 310), Diagnostic Trouble Code/Symptom Chart in the Workshop Manual. Otherwise, INFORM the vehicle owner that it is important and necessary to immediately install the fuel filler cap after every refueling event.

HX65 DTC P1451 OR P0446: CHECK VPWR VOLTAGE TO CV SOLENOID

• Key off.
• Disconnect canister vent (CV) solenoid.
• Connect a non-powered test lamp between CV and VPWR circuits at the CV solenoid harness connector.
• Key on, engine off.
• Attempt to close and open CV solenoid driver in PCM by accessing Output Test Mode.
• Select ALL OFF mode.
• Cycle START button ON and OFF, and observe the test lamp.

Does the test lamp cycle on and off (light up and turn off)?
Yes No
KEY OFF. GO to HX66 . For test lamp always off :

GO to HX67 .

For test lamp always on :

KEY OFF. GO to HX70 .

HX66 CHECK CV SOLENOID RESISTANCE

• Measure CV solenoid resistance.

Is resistance between 48 and 65 ohms?
Yes No
Unable to identify fault at this time. GO to Z1 . REPLACE damaged CV solenoid. COMPLETE an EVAP system leak test at the evaporative test port to VERIFY that a leak did not occur during component replacement. FOLLOW the Vehicle Preparation for Monitor Repair Verification Drive Cycle and COMPLETE an Evaporative Emission Leak Check Monitor Repair Verification Drive Cycle (REFER to Section 2, Drive Cycles ).

HX67 CHECK FOR OPEN VPWR CIRCUIT BETWEEN CV SOLENOID AND POWER RELAY

• Measure voltage between VPWR circuit at the CV solenoid harness connector and battery negative post.

Is voltage greater than 10.5 volts?
Yes No
KEY OFF. GO to HX68 . KEY OFF. REPAIR open circuit.

HX68 CHECK VPWR CIRCUIT FOR OPEN IN HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Measure resistance of VPWR circuit between PCM harness connector pin (or for 150 PIN PCM, the VPWR fuse to the power relay) and CV solenoid harness connector.

Is resistance less than 5.0 ohms?
Yes No
GO to HX69 . REPAIR open circuit.

HX69 CHECK CV CIRCUIT FOR OPEN IN HARNESS

• Measure resistance of CV circuit between PCM harness connector pin and CV solenoid harness connector.

Is resistance less than 5.0 ohms?
Yes No
KEY OFF. REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPAIR open circuit.

HX70 CHECK CV CIRCUIT FOR SHORT TO PWR GND IN HARNESS

• 
  Note: Refer to the PCM connector pin numbers in the beginning of this pinpoint test.
  
• Disconnect PCM.
• Disconnect scan tool from DLC.
• Measure resistance between CV circuit at the CV solenoid harness connector and battery negative post.

Is resistance greater than 10,000 ohms?
Yes No
RECONNECT scan tool. GO to HX71 . REPAIR short circuit.

HX71 CHECK CV CIRCUIT FOR SHORT TO PWR OR CHASSIS GND IN HARNESS

• Key on, engine off.
• Measure voltage between CV circuit at the PCM harness connector and chassis ground.

Is voltage less than 1.0 volt?
Yes No
KEY OFF. REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). KEY OFF. REPAIR short circuit to VPWR, VREF or chassis ground.

HX76 DTC P0460, P0462 OR P0463: CHECK FUEL TANK LEVEL VOLTAGE RANGE

• 
  Note: For Focus, Escape, Mustang, LS6/LS8, Thunderbird, Town Car, Windstar, Explorer/Mountaineer, Aviator, 4.6L/5.4L E-Series, F-Series, Expedition/Navigator/Blackwood and Excursion applications, do not continue with step HX76. Instead, go to Instrument Cluster Section 413, fuel level indicator or Rear Electronic Module (REM) diagnosis in the Workshop Manual.
  
• Key on, engine running.
• Access fuel level input voltage (FLI) PID.

Is the fuel level input voltage (FLI) PID reading between .25 and 4.5 volts?
Yes No
GO to HX77 . GO to HX80 .

HX77 CHECK FOR FUEL TANK FLOAT LEVEL RESPONSE

• Key on, engine off.
• Observe the FLI PID.
• If fuel level is under one quarter (25% on FLI PID), add fuel (7.57 to 11.36 liters [2 to 3 gallons]) to the fuel tank.
• If fuel level is greater than three quarters (75% on FLI PID), drain (7.57 to 11.36 liters [2 to 3 gallons]) fuel from the fuel tank.

Did the FLI PID indicate a movement upward or downward as fuel is either added or drained?
Yes No
No concern found at this time. GO to Z1 for possible intermittent condition. (Frequent filling of the fuel tank without allowing fuel level to drop below the full mark may contribute to a P0460 DTC.) KEY OFF. REFER to Instrument Cluster Section 413 in the Workshop Manual for inoperative fuel level sender.

HX80 CHECK FLI CIRCUIT VOLTAGE AT FP MODULE

• Disconnect the instrument cluster connector to the fuel gauge. (Refer to Instrument Cluster Section 413 in the Workshop Manual or Wiring Diagram manual for cluster connector configuration.)
• Key on, engine off.
• Measure voltage between FLI circuit at the FP module harness connector and battery negative post.

Is voltage greater than 5 volts?
Yes No
KEY OFF. GO to HX81 . KEY OFF. GO to HX82 .

HX81 CHECK FLI CIRCUIT FOR SHORT TO VPWR IN HARNESS

• Disconnect PCM.
• Key on, engine off.
• Measure voltage between FLI circuit at the FP module harness connector and battery negative post.

Is voltage greater than 10.5 volts?
Yes No
REPAIR short circuit. REPLACE PCM (REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ).

HX82 CHECK FLI CIRCUIT FOR SHORT TO PWR GND IN HARNESS

• Disconnect PCM.
• Measure resistance between FLI circuit at the PCM harness connector and battery negative post.

Is resistance greater than 10,000 ohms?
Yes No
GO to HX83 . REPAIR short circuit.

HX83 CHECK FLI CIRCUIT FOR SHORT TO CASE GND IN HARNESS

• Measure resistance between FLI and CASE GND circuits at the PCM harness connector.

Is resistance greater than 10,000 ohms?
Yes No
GO to HX85 . REPAIR short between FLI and CASE GND circuits.

HX85 CHECK FLI CIRCUIT FOR OPEN IN HARNESS

• Measure resistance of FLI circuit between PCM harness connector and fuel pump (FP) module (pigtail) harness connector.
• Measure resistance of FLI circuit between PCM harness connector and the instrument cluster fuel gauge harness connector.

Is each resistance less than 10.0 ohms?
Yes No
GO to HX86 . REPAIR open circuit.

HX86 CHECK CASE GND CIRCUIT FOR OPEN IN HARNESS

• Measure resistance of CASE GND circuit between PCM harness connector and FP module (pigtail) harness connector.
• Measure resistance between the CASE GND circuit at the PCM harness connector and the fuel gauge ground at the instrument cluster fuel gauge harness connector.

Is each resistance less than 10.0 ohms?
Yes No
REFER to Instrument Cluster Section 413 in the Workshop Manual (reference: Wiring Diagram manual) for fuel gauge diagnosis. REPLACE fuel gauge or REPAIR as necessary. Then RERUN Quick Test. If DTC P0460, P0462 or P0463 are still present, REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). REPAIR open circuit.

HX88 CHECK FUEL CAP LAMP ALWAYS ON W/O DTCS

• Disconnect PCM.
• Key on, engine off.

Is the Check Fuel Cap Indicator Lamp OFF with the PCM disconnected?
Yes No
KEY OFF. REPLACE PCM (REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). The PCM has not attempted to ground the circuit between the Check Fuel Cap Indicator Lamp and corresponding PCM pin. This has not turned the indicator lamp ON. REFER to Instrument Cluster Section 413 in the Workshop Manual.

HX89 CHECK FUEL CAP LAMP ALWAYS OFF W/O DTCS

• Key off.
• Disconnect the Check Fuel Cap Indicator Lamp harness connector at the instrument cluster.
• Disconnect PCM.
• Measure resistance between PCM harness connector pin (refer to Fuel Cap Off Indicator Lamp PCM Pin Table at the beginning of this pinpoint test for correct pin number) and Check Fuel Cap circuit at the indicator lamp harness connector.

Is resistance less than 5.0 ohms?
Yes No
REFER to Instrument Cluster Section 413 in the Workshop Manual to diagnose instrument cluster and Check Fuel Cap Bulb. If OK, REPLACE PCM (REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) ). VERIFY repair by turning key to ON position (lamp will turn OFF in 3 seconds). REPAIR open circuit. VERIFY repair by turning key to ON position (lamp will turn OFF in 3 seconds).