Good luck, looking forward to the pics and hearing the result.
1 - 9 of 9 Posts
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I did have a little help, lol and it wasn't a relay fault! the PCB had a faulty "Through plate" on it. this is a small copper tube inserted into the PCB where a track changes from one side of the board to the other, it wasn't conducting power so the control chip for the relay (output from pin 14) wasn't able to get to the relay coil, so we soldered on a bypass wire and hey presto...
look at below pics for brief description...
Seat removed and cover off of BeCM showing the sunroof relay
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this is the spare BeCM (thanks again Rick) that we removed the relay from to see whats going on under it, follow the white line from A to C this is the track feeding the relay coil from the "Through plate" its supplied from under neath from the ic chip leg 14 shown here as "B"
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We found details of the relays pin outs here http://www.bmwgm5.com/GM5_FW_Relays.htm this also made working out the schematics a lot easier as well
this is the under side of the BeCM PCB and again the white line shows the start and end points of the track from ic chip leg 14 (B) to the "Through plate" "A"
![]()
So we soldered a wire from C (relay) to B (ic leg 14) bypassing A (Through plate) completely. the strange thing is the old BeCM i was given (thanx again Rick) had exactly the same fault as mine did, the "Through plate" being unable to conduct electricity.........so maybe this is common cause of sunroof failure, maybe???
anyhow i have to offer a huge thank you to my mate Stuey, http://www.supradupra.com as without his help i probably would have been a little stumped, and yes just a little, lol, thanks Stuey.
look at below pics for brief description...
Seat removed and cover off of BeCM showing the sunroof relay
this is the spare BeCM (thanks again Rick) that we removed the relay from to see whats going on under it, follow the white line from A to C this is the track feeding the relay coil from the "Through plate" its supplied from under neath from the ic chip leg 14 shown here as "B"
We found details of the relays pin outs here http://www.bmwgm5.com/GM5_FW_Relays.htm this also made working out the schematics a lot easier as well
this is the under side of the BeCM PCB and again the white line shows the start and end points of the track from ic chip leg 14 (B) to the "Through plate" "A"
So we soldered a wire from C (relay) to B (ic leg 14) bypassing A (Through plate) completely. the strange thing is the old BeCM i was given (thanx again Rick) had exactly the same fault as mine did, the "Through plate" being unable to conduct electricity.........so maybe this is common cause of sunroof failure, maybe???
anyhow i have to offer a huge thank you to my mate Stuey, http://www.supradupra.com as without his help i probably would have been a little stumped, and yes just a little, lol, thanks Stuey.
1 - 9 of 9 Posts
