Getting a code that indicates the PCM is bad on my '02 GC. It has just under 68k miles on it. The PCM has an 8/80 warranty under the Federal Emmisions Warranty. Does this mean the PCM is still under warranty or did it run out when my GC passed 8 year's old??

 

Check your state emissions warranty laws, it may be covered, but I doubt it. What is the code? PCMs do not fail very often, just because the code mentions the PCM it does not mean you need to replace it. Like when you have an O2 sensor code like "O2 sensor lean bank 1". Most people replace the O2 and think they're done, but it usually means there is a vacuum leak or a fuel pump problem. The codes are only clues of where to start looking, not pinpointing the exact problem.

 

The code is P0601. I've been told it's a PCM checksum error code & the the PCM must be replaced.

 

I just looked the DTC up and this is a rare case in which it does actually tell you the part is bad. But you may not need to replace the PCM, maybe it just needs to be reprogrammed (aka flashed). I would check with the dealer before you lay out any cash on replacing the PCM.

 

Is the PCM the box, roughly 10"x10" next to the coolant resevoir mounted on it's side between the resevoir & the engine? I was told I would need the part number that is on the label under the connectors to get a new one but this device doesn't have a label. It has cooling fins on the top as mounted but the replacement units I see on the net don't appear to have cooling fins so I'm not sure I'm looking atthe right device.

 

My 95 has the PCM on the passenger side of the bulkhead (firewall), but I'm not sure if the 2002 is mounted in the same place.