AC issues

[aloo1]

Can sits for couple months at a time then gets driven about 10 miles then sits again. Negative cable gets disconnected each time it sits. AC was recently recharged about a year ago. Last time (a few months ago) when I drove it, the AC worked fine.
Tried to drive it yesterday and ac won't blow cold. When I crank the car it pauses, turns over once and the cranks so the battery may not be very strong. Would that affect the AC or compressor engaging?
Any other ideas?
This happened a few years ago and it was a broken line that fed into the fire wall. Repaired that and it worked fine, so I checked that line and it's still good.

 

[gt347mustang]

Put gauges on it

 

[aloo1]

Put gauges where? On the battery to check voltage?

 

[gt347mustang]

Put gauges where? On the battery to check voltage?

AC pressure gauges

 

[aloo1]

AC pressure gauges

ahh gotcha. My buddy works in hvac so maybe he can help me with that. If it is shown to have good pressure, then am I looking to the compressor not kicking on? If so, could that be caused by a weak battery?

 

[gt347mustang]

Doubt it.

 

[IA-SteveB]

If you have good pressure and the compressor won't kick in, the next thing to check is the pressure switch. Check the pressure before you do anything though.

You can pull the plug on the switch and jump the terminals in the plug with a paper clip or something similar. If the compressor kicks in then it is more than likely the switch itself. The switch is on the accumulator on the passenger side of the car (little black cannister). Unplug the wire from the pressure switch it and jump it while the car is running and the AC is turned on in the car.

The pressure switch is basically there to prevent the compressor from engaging when the pressure is too low. It would burn itself up. That's why you need to check the system pressure first because that could be the problem right away, i.e. low refrigerant.

 

[aloo1]

If you have good pressure and the compressor won't kick in, the next thing to check is the pressure switch. Check the pressure before you do anything though.

You can pull the plug on the switch and jump the terminals in the plug with a paper clip or something similar. If the compressor kicks in then it is more than likely the switch itself. The switch is on the accumulator on the passenger side of the car (little black cannister). Unplug the wire from the pressure switch it and jump it while the car is running and the AC is turned on in the car.

The pressure switch is basically there to prevent the compressor from engaging when the pressure is too low. It would burn itself up. That's why you need to check the system pressure first because that could be the problem right away, i.e. low refrigerant.
View attachment 1502562

After doing some more researching I've come across post that express what you have said. I'll jump it first but even if it kicks on when I jump it, that doesn't mean it's a bad switch if the pressure is low correct? If the pressure is too low the switch is doing its job and it won't kick over. Jumping it is just to test if the compressor is functioning at all right?

 

[bryantaylor]

the WOT relay in the BCM is known to go out also.

 

[ashleyroachclip]

Aloo1you are correct .
With the gauges connected , and the low pressure switch h jumped , and compressor on , you will be able to determine if the charge is low , and add more at that time.