Since this past fall i've been trying to get my sisters cavalier fixed. It started with a no spark condition. So i replaced the ckp, coils, and the ICM, to no avail, then finally one day i had the brilliant idea of checking the PCM. Long story short, it came out in 2 pieces and was more corroded then you can imagine! Along with that, the plugs were also very corroded. So i spliced in 3 'new' junkyard PCM plugs, along with a pcm. Finally the car starts, but only for 2 seconds before passlock shuts her down. I tried the 10 minute re-learn procedure, and also had the pcm reflashed, but its not recognizing the re flash! Anti-theft still shuts the car down. I'm at a loss now. If anybody can give me some suggestions/help, i would really appreciate it. Should i be testing for continuity/resistance in some wires between the ignition switch/ICM/PCM related to the passlock??

 

A little more info would be nice....year, engine, and aftermarket mods?

 

Sorry, should've included info... 96 cav, manual with the 2.2, i believe all the ecu's were the same in 96, unlike some of the other years, but i'm sure you guys know more than i do. No aftermarket mods what so ever. It is the base model, no extra options.

 

any ideas guys??

 

can you explain the 10 minute re-learn procedure you used exactly?
Who reprogrammed the PCM for you?
Did the donor car have the same motor\year?
part numbers on both the old and new PCM match?
I can't remember the PCM's exact configuration, but are these the ones with the removable PROM under a panel on the PCM? If so you MUST make sure the prom stays with the vehicle....do not use a donor PROM

 

The general procedure i used was to leave the ignition on the 'on' position for a significant period of time. You are supposed to wait until the security light starts flashing i believe. Then you can proceed to turn on the car, and if it doesn't shut down, then it has successfully been 'reset'. I had a fellow reprogram it, or re-flash it as people sometimes call i guess, with a snap on computer where you have to input your vin etc.. and wait until it basically clears the old codes and puts in the ones for your car. The donor car had all the matching numbers and matching options. Thanks for the advice on the prom, i will check that right away, i know there is a panel on there!

 

Ok so here's the scoop. It is a different PCM like i said, and i had swapped in the original PROM chip, i just forgot since i did it so many months ago. I think it should be fine to have a different PROM chip if you Flash it though shouldn't it? I think your suggestion must be if you dont plan on re-flashing. The only problem is that the old pcm was in such bad condition when removed that i suspect there could easily be some type of damage to the original PROM from being in the elements! So i think i might need to try a different PROM, but maybe you can let me know if thats not a good idea.

 

Did the light stop flashing after the 10 minutes? When you start it now, after it stalls does it begin to flash?

If you are going to buy a new PROM, and you have someone to prgram it for you, then you should be ok

 

Hey shawn, sorry it's taken me a while to get back. I havent had time to work on the car, i really just need about freezing temps to work with the wires... Anyhow, the light doesnt even flash, it just simply stays on permanently. When i try the whole relearn procedure, it doesnt change, but the car can always start up for about 1-2 secs, then shuts down with the light flashing for a second or 2, then back to a solid anti theft light. I may have to wire in something to fool this anti-theft. The diagnostic unit could not even reformat my pcm for the vehicle, so i think the easiest route may be bypassing the passlock.