I not been on here for ages but thought other P38 owners may be have the same fault with there BeCM affecting the sunroof as me, and its fixable without replacement of BeCM
My sunroof packed up in December 2005 stuttered and died when opening and not worked since, i swapped out switch pack and roof motor and checked continuity of the cables from BeCM to switch pack and BecM to roof motor.. no problems found so i had to assume its the BeCM
i managed to pick up a old defective BeCM from Rick the pick (thanx Rick) for spares thinking il need a relay
Seat out and BeCM exposed
Cover off
Sunroof relay located
This relay is powered by the bottom of the 4 chips to the right of the pic
The 3rd and 4th pins from the top left of the chip send power to the 2 coils in the relay, one for open and one for closed, (pins 13 and 14) theres a through plate in the PCB just under the bottom left corner of the relay, this is where the track go through the PCB, this is where the problem was, it wasn't conducting electricity through the board.
info on the relay and its operation can be found here BMW E46, E83-X3, E52-Z8 GM5 Front Window Relays V23078-C1002-A303 this proved very valuable in working out what pin did what on the BeCMs PCB
The pic below shows the through plate as A and the track runs under the board from the chips pin No 13 marked as B
The above pic was of the spare BeCM i had and this BeCM had the same problem as mine, so theres a good chance it will be on others too, all that was needed to repair it was a wire soldered on the underside from C to B bypassing A completely........its the green line on the pic below this is pin 13 of the chip to the opening coil of the relay, the red line is pin 14 to the closing coil of the relay this was ok...
I hope this helps someone.......and i now have back full closure of windows and sunroof from keyfob remote, yeh!!
My sunroof packed up in December 2005 stuttered and died when opening and not worked since, i swapped out switch pack and roof motor and checked continuity of the cables from BeCM to switch pack and BecM to roof motor.. no problems found so i had to assume its the BeCM
i managed to pick up a old defective BeCM from Rick the pick (thanx Rick) for spares thinking il need a relay
Seat out and BeCM exposed
Cover off
Sunroof relay located
This relay is powered by the bottom of the 4 chips to the right of the pic
The 3rd and 4th pins from the top left of the chip send power to the 2 coils in the relay, one for open and one for closed, (pins 13 and 14) theres a through plate in the PCB just under the bottom left corner of the relay, this is where the track go through the PCB, this is where the problem was, it wasn't conducting electricity through the board.
info on the relay and its operation can be found here BMW E46, E83-X3, E52-Z8 GM5 Front Window Relays V23078-C1002-A303 this proved very valuable in working out what pin did what on the BeCMs PCB
The pic below shows the through plate as A and the track runs under the board from the chips pin No 13 marked as B
The above pic was of the spare BeCM i had and this BeCM had the same problem as mine, so theres a good chance it will be on others too, all that was needed to repair it was a wire soldered on the underside from C to B bypassing A completely........its the green line on the pic below this is pin 13 of the chip to the opening coil of the relay, the red line is pin 14 to the closing coil of the relay this was ok...
I hope this helps someone.......and i now have back full closure of windows and sunroof from keyfob remote, yeh!!
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