so my bro-in-law drives an '06 cobalt... it died driving across town the other day... it flashed something along the lines of "drivetrain malfunction" or something along those lines...
he not knowing cars AT ALL saw that his oil % is down to 6% and ran to snag a quart of oil... about that time I showed up... checked the oil and it's all good... hopped into the car and it cranked right up... CEL was on though... drove it over to autozone to pull the code... and we get
"p0601 ign control module mem check sum error"
give the guy back his computer and get ready to drive home... it starts and immediately dies and shows that same malfunction error on the dash as it had for him... I went and honestly unsure of what was going on jiggled the wires on the coil (i didn't have any tools so not much else I could do)... the car cranked right up... got it home and it's been parked seance...
anyone have any ideas on what it would/should/could be?
thanks guys
mark
ww
Dork
3/20/09 12:24 p.m.
Not knowing GM's or Cobalts at all, I would say his ICM is going bad. Is it still under drive train warranty? It's only been 3 years... If so, I would have dealer check it out.
@ 65k miles i don't think it's under drivetrain warranty anymore... but i've seen the emissions bit to cover 8/80k... problem for that is the dealer won't give any info on it beyond the "bring it in for diagnosis" which is $85... if they find it to be a warranty thing they take care of it... if not then the money is gone... and the ignition control module is all of $70 to start with from rock auto...
teh inTarweBb said:
CAUSE:
AN INTERNAL RESONANT FREQUENCY INDUCED BY A SET OF DIODES CAUSES THE PCM TO FAIL THE SELF TEST (CHECKSUM ERROR).
CORRECTION:
THE PCM DIODES WERE CHANGED SO THAT THEY OPERATE WITH A DIFFERENT RESONANT FREQUENCY WHICH ELIMINATES THE CHECKSUM ERROR. PCM'S WHICH HAVE AN EIGHTH DIGIT OF FIVE OR LESS (AS OUTLINED BELOW) WILL HAVE TO BE REPLACED.
Score a used computer and have it flashed
Nay, nay. A P0601 checksum code is a PCM (Powertrain Control Module) problem that's under 8/80 emissions. Federal law prohibits charging for diagnosis of an 8/80 emissions item (yet another way techs get screwed but I'll shut up now.) An ignition module is a rather dumb piece of electronics, basically an amplifier and would not set a checksum error.
