PCM - powertrain control module went out!

[deltadave]

Maybe you guys can help me out. My truck quit running, technician said PCM is out; not reading the camshaft sensor consistently. New one is $1,469!! I have been searching and searching online with little luck. Any ideas? Also, it has to be flashed ... can that be done out of the truck or not?

Thanks!!! Dave

[minisub]

What kind/year of vehicle are you talking about?

[deltadave]

Sorry. 2005 Duramax. I see lots of PCM programmers, but that won't do me any good with a bad PCM! I think I found one online at 1stchevyparts for about $860.

Thanks, Dave

[gotdesl]

Could the technician give you any idea why the PCM went out?

[duratothemax]

call Guy at SoCal Diesel. He can get you an ECM for like ~300 bucks.

FIRST...make sure you are diagnosing it correctly. It is very rare for an ECM to actually go bad...more likely its something in the wiring, the CKP/CPS sensors themselves, OR the pin that aligns the CKP reluctor wheel on the crankshaft is sheared, giving the ECM an incorrect reading.

ben

[McRat]

Used PCM's are about $400 on the open market. Might check with SoCalDiesel.

But I'd also be checking out a second opinion. Yes, PCM's fail, but it's pretty rare.

I'm trying to understand how he knows it can't find the crank position sensor if the ECM is dead.

[McRat]

More:

I would check the "bale connectors". These are the two large black connectors with gray levers on the driver's side top of engine. If the pins push in (common) it can do such a thing. Pull the pins back out with needle nose.

[deltadave]

Thanks guys. I'll check SCD. The PCM didn't fail, it intermittently reads the crankshaft sensor.

[minisub]

Check the harness for rub-through while you're at it.

[duratothemax]

Originally Posted by deltadave

Thanks guys. I'll check SCD. The PCM didn't fail, it intermittently reads the crankshaft sensor.

did the dowel pin that keys/clocks the CKP reluctor wheel on the crank shear? Pull the CKP sensor and try to wiggle the reluctor wheel with a screwdriver.

[JustinD]

Pcm is mounted on drivers side front below the battery right?

[McRat]

Yes.

[deltadave]

I have an email into SCal Diesel. I assume the service shop already checked the pins, harnesses connectors etc. I stopped by there several times and they had all their scan tools attached and were diagnosing it. Maybe I should have taken it to the GM dealer, but I figured I'd get screwed there. Does anyone know if you have to have the new PCM in the truck to have it flashed on this model?

[Kat]

Originally Posted by deltadave

I have an email into SCal Diesel. I assume the service shop already checked the pins, harnesses connectors etc. I stopped by there several times and they had all their scan tools attached and were diagnosing it. Maybe I should have taken it to the GM dealer, but I figured I'd get screwed there. Does anyone know if you have to have the new PCM in the truck to have it flashed on this model?

If you buy it from Guy he can flash it to your vin# before he sends it out

[deltadave]

Thanks for the lead on SCal Diesel guys! You saved me over a $1,000! Guy set me up with a Powertrain control module (PCM) for a great deal and was able to bench flash it so all the shop has to do is put it in. He drop shipped it to my service shop. Of course that means I didn't have to tow my truck to the GM dealer, pay them for diagnosis, or take the PCM to them to beg them (or pay them) to flash it.

My shop swears it's the PCM, so we'll see if they're right. I did a ton of searching for GM parts, PCMs, recyclers, etc with very little luck until I found this site. The best I found was about $800 plus shipping and it wasn't even flashed. Hopefully if someone else has a PCM issue on their Duramax 6.6 diesel in the future they will search Google or Yahoo like I did, then find this site, this thread or Guy at SCal Diesel 661-775-5620 socaldiesel.com. Thanks, guys!