How hard is it to change the Body control module on a 2002 coupe. Besides plugging in the new one, what is required?

 

Changing the BCM is easy...a couple harness connectors and out she comes...the hard part is having to program a new one...if you don't have a Tech 2 or a scan tool with programming capability best to take maybe find a mobile mechanic that does programming and let him do it !!...this is a vid but on a 2005 C6 BCM R&R... Keith Defazio (New Level Auto) is a LEGEND around this area for diagnostics and programming.

 

Thanks for the information. I am having a problem with my rear hatch not opening. I traced the wires to the BCM and unplugged it and jumped the wires and the solenoids worked. I tested the button, relay (i even changed the relay and the fuse) and it still doesn't work. Everything else seems to work alright. I am at a loss.

That being the case, that proves the wires, relays, fuse and button all are working properly. What else could be the problem?

 

Have you checked Fuse 32 ? I guess this input to the BCM terminal D9 initiate the opening if the rear hatch
( this is 2001 schematics but it should be similar on a 2002

 

Good morning and lets get this hatch working !!...OK !!....I'm assuming you have a wiring schematic ??...you might have to make yourself a jumper wire to fit into the relay terminal block....remove relay 39 in the IP fusebox...looking at the relay straight on jump the top left and bottom right terminals...if power (power is HOT AT ALL TIMES at the relay and fuse 26 is good) and MOST importantly ground are good (G302...right B pillar) the hatch should release !!...that proves that the LOAD side of the circuit is good !!...if no luck take a test light connected to a good ground...test light should light when connected to the top left terminal...if power good now take 12 volt test light connected to battery POSITIVE...touch the test light to the lower right terminal...if ground is good test light will light...I'm betting the hatch will release when jumping the 2 terminals !!...this is how you would test the LOAD side of the circuit...if the jumpering works we will have to work on the CONTROL side of the circuit.

To check quickly that the CONTROL side is good (excluding the BCM) remove the BCM middle connector...there is a light blue wire...4th from the end...with your test light connected to a good ground touch the tip of the test light to the connector pin...the hatch will open if the wiring from the BCM on the control side works (pic enclosed) and that the control side of the relay works...the BCM may not be proving this ground so you will have to check what oelarse recommended...check fuse and integrity of the wire from the switch to BCM...let us know !!

 

The information that you provided was very helpful. I followed the instruction as you listed them. The BCM has power going into it but not coming out of it. The jumper in the plug caused the solenoids to function. The button, when pressed, put power to the BCM. What else could it be? I am frustrated but greatly appreciate your help.

 

Ok, so you jumpered pins 87 and 30 and the hatch unlatched ??...what happened when you applied the ground to the BCM as shown in the picture ??...did the hatch unlatch ??...if you have not this you have to do this so we have some direction !!...where are you checking the BCM for this power ??

ps...I will have to look at the rest of the circuit...will do this a little later !!