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Chevy366
December 20th, 2012, 07:56 AM
Wife got a scare, truck died on her, she restarted it and the CEL was on, I read the DTC codes and P0601 popped up, PCM EEPROM (P0601 ENGINE CONTROL MODULE CHECKSUM ERROR) WTF. Funny a guy asked me a few months back about his TB (2004) experiencing the same exact code P0601 and asked if I could re-flash the PCM, I told him I could but would not guarantee success.

2 in a known time period weird. Bad PCM EEPROM run?

Addition ; Visited Trailvoy site and see there are lots more.
112,000 miles past Emission warranty period. :bawl:

joecar
December 21st, 2012, 04:17 PM
Which PCM is this...?

ScarabEpic22
December 21st, 2012, 06:50 PM
P12.

Interesting to hear, my P10 has been just fine. What .cal or .calz files are you using to tune it, still using some of that old mystery beta stuff or production?

Chevy366
December 31st, 2012, 07:51 AM
P12

Chevy366
December 31st, 2012, 08:00 AM
P12.

Interesting to hear, my P10 has been just fine. What .cal or .calz files are you using to tune it, still using some of that old mystery beta stuff or production?
I am going to full flash and see what happens, production file.
Don't think is anything to do with EFILive or its flashes, seems a lot of PCMs get this error, even Dodge.
Was hoping for some insight on the EEPROM, have read that the EEPROM has gotten full and is throwing this code, like, unlikely?

GMPX
December 31st, 2012, 01:21 PM
Try reading it first, if there is a checksum error you'll see it in the warnings when the read is done.

Chevy366
January 1st, 2013, 11:50 AM
Try reading it first, if there is a checksum error you'll see it in the warnings when the read is done.

Okay, read the PCM (inane TBs have to hit start position without starting, and PCM will read) I did not see any checksum error generated.
Had persistent code that was for the left speaker ground, I finally took care of that, left rear speaker was dead, can another bus cause a fault in the PCM such as the ECM?

Chevy366
January 1st, 2013, 02:35 PM
Got to see it happen in person, we went for a drive, DTC gets set and engine dies, turn key off for a few seconds and engine starts right back up, goes for a several more miles then off again goes the engine, code is still the P0601.
Going to do full flash tomorrow, with fingers crossed.

GMPX
January 1st, 2013, 03:39 PM
A quick Google and it seems to be a common issue with both the P10 & P12 Trailblazer, though there doesn't appear to be any GM updates as a fix for it.

Chevy366
January 2nd, 2013, 11:17 AM
A quick Google and it seems to be a common issue with both the P10 & P12 Trailblazer, though there doesn't appear to be any GM updates as a fix for it.
Yeah seems to be a common problem in all makes.
I took the PCM out, cleaned the connections both harness and PCM, didn't really look bad at all, did the Trailblazer Flash Dance (have to figure out the certain process to make a successful flash) and did a successful "full flash". I used the file I read and just flashed it back in as a .ctz extension with no modifications to tune.
Funny memory took a full flash fine no errors, EEPROM must be totally rewritten or else something else is screwy, shows 992k out 1024k flashed, I know that the full EEPROM memory allotment is not used.
Will see what happens.

Chevy366
January 2nd, 2013, 03:52 PM
Update ; Took TB out for drive, no DTC or dying. Not going to say "fixed" just yet, but looking good.

Chevy366
January 14th, 2013, 09:05 AM
Fixed. SO if you get a P0601 code on a 06 TB just full flash and it seems to fix it. [after checking to make sure of no checksum error]
I did notice when I was inspecting the PCM that a rubber bumper (not a baby bumper) was loose, I used some double sided tape to reattach it, the rubber bumper applied pressure on the PCM housing as a dampener and a spacer to make the PCM snug in the PCM mount.
PCM had been rattling around in the mount, indicated by the wear marks on the back of the PCM.