so I heard that replacing a bcm will not work off a junk yard donor due to vin issues but would it work if you replaced the bcm and pcm from the same donor car with hopefully the same options as my car? have any of yall done it?(2000 monte ss 3.8l btw)

 

Ive heard of people using jy bcms with no issue(in fact i have a friend with a 2000 gtp running a jy bcm)

 

A wrecking yard PCM/BCM is not plug-n-play. Your vehicle VIN and all options your car has must be programmed into it. Otherwise you will be left in a no-start situation.

 

So a 2000 grand prix and a 2000 monte are THAT different?

 

First, there is a LOT different about a Monte and Grand Prix when you talk about electrical stuff (not sure how much that impacts the BCM).

It's not how different a Monte and Grand Prix are with the BCM. The BCM requires programming for your car. It's options, VIN, anti-theft information. I believe a junk yard BCM can be used, but if memory serves, last I read in the shop book, a BCM needs programmed with a GM Tech II.

If you plug a BCM in and try to start the car, nothing will brake, worst case, nothing will work though. I don't know what happens if you just plug a donor BCM into the car, so I can't say what will and will not work. Mike (03SSLE) I believe works in a shop, if he's changed BCMs before, he would have better guidance on this subject.

 

thanks for the info guys
what components need to match up if anybody knows cause really I wanted to swap both the bcm and pcm from the same donor. I heard of people swapping them with saturns all they had to do was the re learn procedure for the key to actually work.

 

I think the next question is, why are you changing the PCM if the BCM is bad?

Let's say you do swap the BCM with a donor. If you are still running the factory radio, theft lock on the radio will probably activate and you are back to having a GM Tech II do work on your car.

 

the only time these parts need to be replaced is if they have failed internally (i.e board burned up)...but if one does need to replace them and used salvage yard parts, you WILL need to get them flashed if they came out of a different car...another idea would be to call a parts store and compare pcm or bcm part numbers...if the part numbers are the same, then all you need to do is have them flashed

 

for some dumb reason im thinking if I get both for super cheap from the junkyard I could just swap them both out so I wouldn't have to program the bcm to match the vins(or do the vins matching up don't matter cause I thought theyd have to match up) and options that my car has. I don't know if im explaining myself right. I always update after having a few.
thanks

 

oh and the reason im swapping(bcm) is because I think its bad I really don't know how to check if its bad so im just on some trial and error.(I say its bad because it used to not wanna start at times while flashing the security light and my interior lights were all fritzy. also I had a drain that would kill my battery forcing me to jump start every 2 days.) still I m just guessing its the bcm that's bad
thanks again