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canbuick 04-19-2014 09:28 PM

I'm still having the problem, but have done some more diagnosis. I've used a power probe to test all fuses. I found that the BCM Power fuse (10A) was dead. I replaced it and it failed right away. As a result, I'm assuming I have a short circuit, but I'm not sure where to start looking.

I tested and did have 12V at the starter. Using the power probe I applied voltage directly to the purple wire on the starter and the car turned over and started right away. It ran for a few seconds and quit. I'm assuming without the BCM fuse (and associated short circuit) it won't continue running.

Any ideas on how to trace the problem that's causing the BCM fuse to keep failing?

Thanks.

Tech II 04-19-2014 10:25 PM

2 Attachment(s)
OK, when you turn key to crank, the starter does not move....however, when you apply power directly to the starter solenoid "S" terminal(purple wire), the car turns over and then dies, because the injectors are not firing because the ECM is not getting a fuel enable signal from the BCM.....

You need a schematic of the BCM, to see if that fuse feeds another circuit besides the BCM......

Which fuse is blowing? What is the EXACT name of the fuse on the fuse block cover?

https://www.gmforum.com/attachment.p...ine=1397960707

canbuick 04-20-2014 01:10 AM

The fuse that is blowing is located under the dash and is labelled BCM Pwr (a 10A fuse).

I assume the most likely source of the problem is the BCM - is there any way to verify that without purchasing a replacement body control module?

jwfirebird 04-20-2014 10:33 AM

unplug the bcm, and put a new fuse in, if it blows its the wiring, if not its in the bcm

canbuick 04-20-2014 03:03 PM

Makes sense - I'll give that a try. Where is the BCM module? Is under the dash?

jwfirebird 04-21-2014 12:05 PM

the manual says under driver side air duct, vertical with 4 plugs on the bottom

canbuick 04-24-2014 08:02 PM

Problem solved - I gave up and took it to the garage today. They verified that the problem was not related to wiring going to the BCM or output from the BCM. Therefore, the short was occurring in the BCM unit itself, hence the reason the 10A fuse to the BCM pwr kept popping. When they pulled it out, the circuit board was melted. The technician said that this isn't uncommon with this vintage of GM vehicles (they had 3 in this morning with similar problems).

They showed me the unit they pulled out and the core of it was seriously scorched. Typically, if it can be refurbished, I would be due for a $160 credit since they can send the old one back - unfortunately, this doesn't look promising for mine.

The fix was to replace the BCM with a refurbished unit. They programmed it and everything is good as new. Total cost $1,012. Ouch! Unfortunately, I don't think this was a job I could have done myself without the proper tool to re-program the BCM (Tech 2 scanner?) and once the BCM is replaced, it will NOT function without being reprogrammed for the specific vehicle.

Anyway - it's warrantied for 40,000km's or 2 years - so I won't have to worry about this issue for a while.

jwfirebird 04-25-2014 07:23 AM

thanks for posting the fix. it looks like the bcm is becoming one of the most expensive parts on the car, sucks

Mike 04-25-2014 07:31 AM

I hate dealers. You got so hosed on this. A/C Delco reman part from rockauto.com is $158. Not for one minute do I believe it takes that much labor to find/remove/install and program. It costs that much to remove a FWD transmission.

Tech II 04-25-2014 10:47 AM

Totally agree with Mike on this one, concerning the cost.....but I disagree on lumping all dealerships together.....


First, have never seen a core rebate on BCM's......second: "The technician said that this isn't uncommon with this vintage of GM vehicles (they had 3 in this morning with similar problems). " Yeah right, why not be more dramatic and say 4?

Don't know what the cost of Canadian parts are, but that job should have not even been half that price....do you have a break down of parts and labor charges(time involved)?


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