PCM problem

[Frostbite545]

Well I'm told its a problem at least:

When I recently installed the PCM I took it to my mechanic. The check engine light had not come on, so i assumed it didnt need a case learn. Turns out that the cars computer is no longer readable by any of the scanners that are used. Additionally, it is bypassing the check engine light. I assume it would be on, if it could.

Anyway, the cars not gonna pass inspection if it cant be read... any ideas? I already emailed DHP.... i pray they actually respond.

[jackal2000]

how can you know that the SES light is being "bypassed" if the PCM cant be read? which is strange in the first place. did you install it yourself? im wondering if some of the pins got damaged somehow.

[Frostbite545]

I'm technically challenged when it comes to cars, as far as I know, I installed it without any pins getting damaged, but ill disconnect the battery and check later. Im only saying what the mechanic said... I may be off a bit, though I know it couldnt be read.

[jackal2000]

this is making some sense to me now. was he trying to download the .bin from the PCM? im fairly certain that DHP has a measure in place to prevent that. otherwise, the PCM could be exploited and other PCMs could be flashed and marketed under a different brand. i dont see how reading the PCM is part of ANY inspection.

[strtrydr]

Arizona does the same thing for their Inspections ... They plug thier computer into the OBD2 port and then try to read the PCM. At least that is what I am assuming they are trying to do.

[jackal2000]

DHP encrypts their .bin's so i guess that would be a problem.

i didnt have an issue when i had my north carolina inspection done. hell, all i can think of now is maybe DHP messed up when they entered your VIN # in the .bin file. i can see how a non-matching VIN could be a problem with their reader. cause the mech typed the VIN on your registration into his computer right? if the PCM has a different VIN there's your problem. thats why you send DHP your VIN in the first place.

[strtrydr]

This posses a big problem for me then ... WTF am I going to do now.

Jackal ... do you think a forced PCM learn off of the DHP PowrTuner would have the same effect since it would keep the Stock PCM. If I could get away with that then that would solve the problems.

[jackal2000]

if i am right about all this then it doesnt matter if the PCM is the one that came out of the factory in your car or not. all that matters is that it has YOUR car's VIN programmed into it.

[strtrydr]

That does make sense ... but would a Forced-Learn from Someone elses DHP PowrTunr have MY car's VIN in it?

[Frostbite545]

I will make sure my mech had the right VIN#, he checked it before he tried to read it, he has done work on the car before, so he should have it right. Ill call DHP and make sure they put the right VIN into the PCM, and that I sent them the right number in the first place lol.

[jackal2000]

Originally Posted by strtrydr

That does make sense ... but would a Forced-Learn from Someone elses DHP PowrTunr have MY car's VIN in it?

the VIN can be programmed via PowrTuner. its one of the options on the "pcm flash" screen. its a drop down menu and has 3 options, one of them being manual input IIRC. i always choose pcm vin on that screen and really dont pay much attention to it.

[strtrydr]

cool ... thanks for the help

[alerored04]

Jackal im not sure if the .Bin file is encrypted anymore. I know when Germ opened my v1.0 pcm up to retune he was able to read the whole file.

[BlackJack]

bah. I've had a GM dealer's scanner used on my car at least 3 times since reprogramming. I doubt it's the encryption causing it to not read. Tell that guy he needs to go buy a new $12,000 scanner, he'll love that.

[jackal2000]

Originally Posted by alerored04

Jackal im not sure if the .Bin file is encrypted anymore. I know when Germ opened my v1.0 pcm up to retune he was able to read the whole file.

with what program?

Originally Posted by BlackJack

bah. I've had a GM dealer's scanner used on my car at least 3 times since reprogramming. I doubt it's the encryption causing it to not read. Tell that guy he needs to go buy a new $12,000 scanner, he'll love that.

scanning is not the same as reading. reading (to me) is the actual downloading of the .bin that is in the PCM to the desktop on your computer.


but like i said a few posts ago. im leaning more towards this as a VIN issue, not encryption.

[Frostbite545]

The PCM code we do does not lock out communications to any scanners.

Either of these problems exist maybe.

1) CIG Lighter fuse is out. I know on most GM vehicles if this fuse is out, the 12v power pin on the OBDII port will not power the scanner.

2) the communication pin on the PCM is bent/bad

3) if hardware #'s didnt match

They go on to say that the most likely is the CIG lighter fuse... where the heck is that, in the fuse access or something ?

[jackal2000]

its under the hood....its like fuse #24 or something. look at the diagram to find it. it should say something like cig/acc. the obd-II port and the cig run on the same fuse so that makes sense.

[Cliff8928]

If i remember right, that fuse powers the +12v pin on the ALDL and is what provides power for the code reader.

[Frostbite545]

Ok well its not the fuse, which was #34, jackal you were close haha, but its fine, I pulled it out and checked, but yeah its not burned out or anything.

I also pulled the PCM out and looked at the pins and connectors, but everything seems to be fine too. It connects in properly and I didnt over-torque it when tightening the bolts.

I'm guessing the only thing left is someone has the wrong VIN# somewhere... should i ask DHP what VIN they have on file for me? And subsequently which one they put on the PCM...

[jackal2000]

its worth a shot. i'll ask on the DHP forum and see what the powrtuner peeps say about it.