1996 GT PATS trouble

[SNVitty]

Hi,
My name is Corey, I'm new to the forum and looking for pats help! I have a '96 gt convertible and I'd like to try to figure out why it's not reading the key.

The Story
I was suffering from denial. I have a 94 f150 running a 351 with ported heads, intake, long tubes, true dual, 4 inch lift, 33in A/Ts, and a few other goodies... and a certain lead footed driver. I was certain I was getting 30 mpg driving all over Texas. Turns out my estimate was slightly off.
I have since come to accept that honesty with ones self is important. I decided I needed a more efficient vehicle. While shopping around I found the perfect solution! A brand new to me 1996 gt convertible! (3x the mpg!) I talked the seller down to $400 because it didn't start and they couldn't figure it out. (In my head, at $400 I could get it and swap in a 302 if I got tired of messing around with the 4.6.) The only thing is the car doesn't run and the theft light flashes.

What I have tried.
At first the car wouldn't turn over, and the fan was constantly running. Figured that out and swapped the CCRM for one that I know works. Something still wasn't right and I pulled the ecm to have a look at it and found out it was for a crown vic with an automatic. -_-

Swapped in a proper ecm, put in a new fuel pump and a good test battery. Everything seems to be working well, the car even turns on and runs for a second. However the car won't stay on and the theft light flashes. After some digging I believe it's the PATS.
I have tried swapping the transciever and the pats unit itself, I have had a locksmith out with a full diagnostic system, tried different keys, all to no avail.

From what I know thus far...
The PATS (Which is type A) is not reading a key. *Note: NOT THAT IT SEES THE WRONG KEY BUT THAT IT DOESN'T SEE A KEY AT ALL. From my research I can tell that it sees no key because the light doesn't flash for 15 minutes (so I can't reprogram it). It only flashes for 60 seconds.
I don't want to need an SCT tuner to use my car at all, but I will if I have to. I have searched so much for the last 7 months and have found no real information for how to address this specific problem. I was wondering if there is anyone that can help me out.

 

[98 svt]

What code is the theft light flashing?
(3 fast blinks, pause, 2 fact blinks for example)

 

[SNVitty]

Hi! No code, just consistent fast flashing for 60 seconds.

Thanks for the reply!

 

[SNVitty]

Also of note is this mystery box underneath the center console...

 

[98 svt]

Also of note is this mystery box underneath the center console...

That box looks like a Speedcal.

 

[SNVitty]

Aaaah, I had no idea and was thinking it may have been a remote starter attempt! This doesn't surprise me because of how many other things the car came with. (equal length headers, hi flow cats, offroad x, bassani longtubes, light bar, intake, etc...) ok, that's good to know!

 

[98 svt]

Yeah, so you must have some gear in the rear too!
That's a good start. Any idea what ratio?

 

[90lx]

It sounds to me like you need to start by programming the key. You will need 2 keys to go through the programming process. Especially since you put another pcm and transponder in it. You need to either use a dealership or independent shop that has IDS. (the ford factory scan tool) Good Luck and let us know how it turns out

 

[Revvv]

I would have a tuner turn PATS off. I hate that system.

Sent from my [toilet] using the svtperformance.com mobile app

 

[52merc]

From everything I've read about PATS, it will not stop an engine which is running. If it starts, for even a couple of seconds, then shuts down, the issue is not PATS. I'd continue to look elsewhere.

 

[crazyespn]

I had the same issue you described. The THEFT LIGHT kept coming on, fans running for no reason etc. Almost acted like my valet key. After tons of diagnosing, it was the ground from the battery to the top of the radiator support above the driver headlight. The wire was very loose. I ended making a new ground connection and also had to replace both battery terminals as they were also loose. After that never had the problem again. Hope this helps, or at least move on to the next solution.