Electrical 97 Mustang Gt Won't Start Pats Problem? Help!

Hi, I recently bought a 1997 4.6L mustang. I got a transponder key with it that I could tell wasn't factory. I had it cloned. The key I got with it broke and the clone key worked for a few days. About 5 days ago the clone key just stopped working the car would start up then die and the theft light would flash. I read about how to reprogram keys for the PATS I system it's equipped with so I tried that. It didn't work, but, I found out that if I left the key in the on position until the theft light went off then I could start it and it would run.

Well after a couple times it stopped working again so instead of starting after the theft light went off it would just crank and not start at all. I had a locksmith come out and they said it had to be the immobilizer or something like that because none of the keys they tried would work so it stopped accepting all transponder codes. Now the car won't even crank I try to start it and it just makes a ticking noise in the engine so i think he messed up the battery since he was fiddling with it while trying to find the problem. I heard these car sometimes have problems with the transceiver wires so I didn't know if those could be the problem or not?

It also has a salvage title from being rear ended i didn't know whether or not that matter. I'd really like to get some help ASAP because the only thing else I can do is tow it to a dealer that will rake me over the coals just to test it before they can even tell if they can fix it because there's no mustang specialized shops around me or any I'm aware of that can help me.

Please help! Thank you.
 
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STOP. put down the tools and walk away. Do not do any more trouble shooting until you are certain that the battery is good and fully charged. Make sure that the battery cables are CLEAN and tight. Then and only then, should you start trouble shooting the POSSIBLE PATS problem.

Note, PATS does not turn off the motor once it starts. So if the motor dies after starting, it's not a PATS issue.

For further proof, turn the key on but do not crank. Does the theft light go off after a 3 second "prove out"? If so, then this is the confirmation that the key was read correctly and PATS is going to allow the motor to start.

Bottom line. Today's cars simply will not run right without a strong battery and charging system. Cut corners here at your own risk!
 
The theft light is suppose to slow blink. It's the reminder that the system is working.

Just wondering what you are expecting to happen if the PATS transceiver has been disconnected? Of course PATS is going to fail.

Turn the key on. Do not crank. Observe all of the lights on the dash. All should be light for the lamp test. Pay special attention to the theft light. Does the theft light turn off after a 3 second "prove out"? IF yes, then the PATS system has read and accepted the key.
 
no it hasn't read the key for almost a week it flashes rapidly for about a minute then turns off. After that e car won't turn over unless I turn the car off then try to start it then it starta up and dies and the cycle continues. I took apart the transceiver and ignition switch to test and see if everything was connected correctly and as far as. I can tell it is. The locksmith that came out said the car wouldn't accept any of the chip keys he tried to use either.
 
Remove everything from the key ring except the key itself. Unlock the door with the FOB or unlock the driver's door with the key.

The request was made to put the key in and turn to run but do NOT crank. Wait to see what the theft light does after the 3 second "prove out".

It seems like you are in a race to crank the car just as fast as possible. Which is destroying any chance to see what the theft light is doing after the "prove out".

As an additional test. Turn the key on/pause/off several times but do NOT crank. LISTEN for the fuel pump to run. Do you HEAR the fuel pump run? If you can not hear the fuel pump run, stop and find out why. If needed, get a buddy to help.
 
What I've done so far:
Checked and replaced all shorted fuses
checked the connection on all the transceiver wires
checked the fuel pump(I can give it gas before it dies so I don't think the fuel pump is the problem)
I don't really know what else to check.
 
For the Theft light on constant the Ford service manual lists:
  • Passive anti-theft system (PATS) control module.
  • Powertrain control module.
  • Transceiver module.
  • Open fuse.
  • Ignition key.
  • J1850 Communications Network
  • Open circuit.
  • Short circuit.
Based upon the information I can gleam from this thread it seems the best guess is that the PATS module is reading the key but NOT accepting as valid. If this were my car, I would re-program the key and try again. For the 96-97 model year there is an end user procedure that can be done to re-program your own keys. It takes 45 minutes to perform and must be done exactly.

The procedure is too long to post. If interested in getting a copy of the Ford service manual for yourself, I maybe able to help. PM if interested.

>>From the Ford manual.
The passive anti-theft system components function as follows:

  • THEFT indicator
    • The passive anti-theft system utilizes the same (THEFT) indicator, (located in the instrument cluster (10849)) that the anti-theft alarm system (if equipped) uses. (Refer to Section 13-11A .)
    • The indicator provides system proveout and operating status to the customer or service technician.
    • The active anti-theft alarm system uses the theft indicator when the ignition switch is turned OFF.
    • When the ignition switch is turned to RUN/START, the passive anti-theft system will activate the THEFT indicator signal ON for two seconds, then OFF to indicate Key Code Received/Vehicle Enabled (programmed key).
Any other THEFT indicator illumination indicates a passive anti-theft system (PATS) concern:

  • THEFT indicator ON two seconds, then OFF one second, then ON continuously indicates key code received/vehicle disabled (Assembly plant use only, less than two keys programmed).
  • THEFT indicator ON two seconds, then flash for one minute, then flash Fault Code 16 ten times indicates key code received/vehicle enabled or disabled (no PCM verification).
    • If vehicle starts, PCM is not working with PATS control module.
    • If vehicle does not start, the J1850 Communication Network may need service. Refer to Section 18-04 for Data Link Diagnostics Testing.
  • THEFT indicator flashes for one minute indicates no key code received. Causes include:
    • damaged key
    • non-encoded key
    • wiring concern
    • PATS module
  • THEFT indicator flashes for 15 minutes indicates key code received/vehicle disabled (key not programmed). Refer to Key Initialization procedure.
 
For the Theft light on constant the Ford service manual lists:
  • Passive anti-theft system (PATS) control module.
  • Powertrain control module.
  • Transceiver module.
  • Open fuse.
  • Ignition key.
  • J1850 Communications Network
  • Open circuit.
  • Short circuit.
Based upon the information I can gleam from this thread it seems the best guess is that the PATS module is reading the key but NOT accepting as valid. If this were my car, I would re-program the key and try again. For the 96-97 model year there is an end user procedure that can be done to re-program your own keys. It takes 45 minutes to perform and must be done exactly.

The procedure is too long to post. If interested in getting a copy of the Ford service manual for yourself, I maybe able to help. PM if interested.

>>From the Ford manual.
The passive anti-theft system components function as follows:

  • THEFT indicator
    • The passive anti-theft system utilizes the same (THEFT) indicator, (located in the instrument cluster (10849)) that the anti-theft alarm system (if equipped) uses. (Refer to Section 13-11A .)
    • The indicator provides system proveout and operating status to the customer or service technician.
    • The active anti-theft alarm system uses the theft indicator when the ignition switch is turned OFF.
    • When the ignition switch is turned to RUN/START, the passive anti-theft system will activate the THEFT indicator signal ON for two seconds, then OFF to indicate Key Code Received/Vehicle Enabled (programmed key).
Any other THEFT indicator illumination indicates a passive anti-theft system (PATS) concern:

  • THEFT indicator ON two seconds, then OFF one second, then ON continuously indicates key code received/vehicle disabled (Assembly plant use only, less than two keys programmed).
  • THEFT indicator ON two seconds, then flash for one minute, then flash Fault Code 16 ten times indicates key code received/vehicle enabled or disabled (no PCM verification).
    • If vehicle starts, PCM is not working with PATS control module.
    • If vehicle does not start, the J1850 Communication Network may need service. Refer to Section 18-04 for Data Link Diagnostics Testing.
  • THEFT indicator flashes for one minute indicates no key code received. Causes include:
    • damaged key
    • non-encoded key
    • wiring concern
    • PATS module
  • THEFT indicator flashes for 15 minutes indicates key code received/vehicle disabled (key not programmed). Refer to Key Initialization procedure.
I know this is most likely a few years too late but worth a shot… I’m having the same issues with a 97… anyway I could get info from the service manual as well?