PCM Programming


#1

Pretty sure the PCM in my 2000 Impala, 3.4L, is bad. The book says than when replacing the PCM, it requires programming. When I installed the replacement PCM, the car ignition system was shot down. My mechanic has no info on this programming. Is this something only the dealer can do?


#2

If your public library system offers ALLDATA I suggest you make them a visit. You can find all of the reprogramming procedures there. GM uses a few different theft deterrent systems on there cars. Being that the 3.4 is very similar to a 3.1 I’d try this:

If there is a light activated on the dash that says “Theft System” or “Security” turn the key until the engine cranks, then back to the “On” position. Leave the system on until the light goes out. (could be 3-10 minutes) When the light goes out, turn the key backward to the off position. Then restart the car. This is the procedure on a 99 Malibu 3.1, Turning the key off after the light goes off is the key element. If you just try to restart from the on position the light will activate again and the time-out will start over.


#3

PCM hardware is often generic and shared between a number of platforms. In those instances, they need to be “flashed” with the programming specific to your car. The trim tables will also be initialized with the defaults from the platform specific programming, making it run better “out of the box”. Some independant shops can do this kind of programming but the dealer should be better equipped to insure that the latest programming changes are included when they program it.


#4

All PCM programning I have done for GM required a PC with correct software and a Tech2 scanner.Including security system programning.


#5

Thanks for the help.