Bought a new PCM for an '06 coupe & the windows do not go down upon opening door.

[ViperperfectionGTS]

The dealer swears it is the correct PCM; it sure seems to be set-up for a convertible. I dont doubt that it is probably the correct PCM, but what do I need to do in order to get the windows to slide down when opening the doors? The PCM that I took out worked perfectly in that respect. Is it because the new PCM has no VIN programmed to it? Thanks sincerely.

 

[USMCLY]

do a reset on the window. Put window all the way down and hit the down button 3x then all the way up and hit the up button 3x and it should reset.

 

[ViperperfectionGTS]

Thanks for the reply. I tried. No such luck.

 

[Roadrunner]

Dealer needs to program the VIN... the VIN tells the car whether it is a coupe or convertible.

 

[Flexx91]

I thought the BCM (Body Control Module) controlled the action of the windows. Maybe there a programming disconnect between the new PCM and your current BCM.

 

[ViperperfectionGTS]

Do the windows go down 1/4" on the convertible when you open the doors? If not, I definately need to get the VIN in the PCM. My old PCM allows the windows to go down perfectly.

I'll research the BCM info to see what can be done with that connection.

 

[USMCLY]

My old viper that was Conv did go down

 

[bmw2nv2000]

BCM controls the windows. Ive been down this road.

 

[ViperperfectionGTS]

So doni simply need to buy a new bcm or do I need to program something? What's the process? The PCM I just took out worked perfectly so this is hard to understand. Thanks

 

[bmw2nv2000]

I really don't understand why windows acting up because of PCM swap. Ive had to swap out a BCM before because windows weren't working correctly. BCM was just acting crazy but a used BCM fix windows 100%. Bad thing is BCM also controls mileage so if you buy an used BCM buy one with close to same miles as your car has.

 

[Viper Specialty]

So doni simply need to buy a new bcm or do I need to program something? What's the process? The PCM I just took out worked perfectly so this is hard to understand. Thanks

You must use a dealer to replace BCM. They will look at the car, confirm the issue, and order a BCM. Upon arrival of the new BCM, they must either install it themselves or you must surrender the old BCM before they will give you the new one. The BCM contains the VIN and Mileage, so they do not want BCM's making it into the market if possible. A Smart Glass issue is indeed a known BCM subsystem, and they should not give you any issues.

I would however certainly correct your PCM VIN issue first, as that can indeed cause bus fault codes- it is however unlikely related to your actual problem.

 

[Roadrunner]

The PCM is the "VIN Master" - The BCM reacts to the VIN being transmitted to determine whether it does the coupe window drop or the convertible window glass drop. But body styles have a drop, but the coupe needs greater retraction to clear the body. When you have a PCM with no VIN, the BCM defaults to convertible drop... and the glass won't clear properly. It is not a connection issue. Just a lack of VIN data issue. Set the VIN, the system will work.

 

[Viper Specialty]

The PCM is the "VIN Master" - The BCM reacts to the VIN being transmitted to determine whether it does the coupe window drop or the convertible window glass drop. But body styles have a drop, but the coupe needs greater retraction to clear the body. When you have a PCM with no VIN, the BCM defaults to convertible drop... and the glass won't clear properly. It is not a connection issue. Just a lack of VIN data issue. Set the VIN, the system will work.

This applies to Gen-4 primarily where VIN is forced and programming is slightly different. The BCM in a Gen-3 is VIN-flashed like the PCM, and it CANNOT be changed no matter what PCM is put in the car with any VIN contained. His BCM should not have spontaneously changed its VIN due to a PCM change, especially a blank PCM. Also, both the Vert and Coupe have a Smart Glass drop, and his car is doing nothing at all. Its a very odd scenario, but I do agree, that PCM VIN should be corrected before doing anything else. It is possible the VIN Blank fault code may be a player in this. But I can assure you, even pulling the PCM out of a Gen-3 completely will have no affect on Smart Glass function.

 

[ViperperfectionGTS]

Can the dealer program the VIN? I have zero confidence in the brain surgeons I've spoke to thus far in town (granted Dallas probably has 10 dealers & I haven't talked to all of them). I hate taking it to the dealer. Would ya'll like me to put the original PCM back in & see if the windows go down? I suspect they will; which I understand makes zero sense.

 

[Viper Specialty]

Yes, they can. You can send it here also if you need to do so.

Yes, putting the old PCM back in and testing the theory is a sound method.