OBC Questions
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- randall977
- Posts: 264
- Joined: Sun Jan 21, 2018 9:52 am
- Location: Oxford, UK
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OBC Questions
I have a UK 85 M635...
I removed some aftermarket audio wiring from under the dash and found that the red/green wires which supply power to the radio, interior lights etc had all been messed with - I repaired and re-joined them all and everything worked...apart from the OBC display - illuminated but no LCD.
Then, a few days later the car wouldn't start, I fiddled with various wires and then it started and ran fine - not sure what I did. I tapped the OBC relay while the car was running to see if the display would come back - it didn't but the car did stall. Is this just because I'm disturbing the immobiliser relay? Is the loss of display just coincidence?
I really need a spare OBC to test with, a new relay is £80, not too bad but I don't want to replace it for nothing. Thanks for any help!
I removed some aftermarket audio wiring from under the dash and found that the red/green wires which supply power to the radio, interior lights etc had all been messed with - I repaired and re-joined them all and everything worked...apart from the OBC display - illuminated but no LCD.
Then, a few days later the car wouldn't start, I fiddled with various wires and then it started and ran fine - not sure what I did. I tapped the OBC relay while the car was running to see if the display would come back - it didn't but the car did stall. Is this just because I'm disturbing the immobiliser relay? Is the loss of display just coincidence?
I really need a spare OBC to test with, a new relay is £80, not too bad but I don't want to replace it for nothing. Thanks for any help!
Re: OBC Questions
'84 M635csi
'86 Lotus esprit Turbo (sold)
'86 Lotus esprit Turbo (sold)
- hornhospital
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Re: OBC Questions
Thank you for that link! I'm going to be the guinea pig. I ordered a repair kit for one of the small OBCs (in my E30). If it works (in other words, if I don't screw it up) I'll get one for the OBC in my 633. Amazingly, the OBC in my far more abused 635 still works!
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
- randall977
- Posts: 264
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Re: OBC Questions
Thanks, it might come to that but I don't to go down that route if that's not the problem. It did work...
- randall977
- Posts: 264
- Joined: Sun Jan 21, 2018 9:52 am
- Location: Oxford, UK
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Re: OBC Questions
Did some more investigation into the lack of OBC display today. Wiring looks okay, can't find a fault - the backlight functions but no LCD characters at all. I can get a new display as TBM's link, but do displays loose their LCD totally and suddenly like this? Is the OBC display the same on an E30? I can get a spare for an E30 quite easily...
Re: OBC Questions
Randall - i have a spare working OBC I can lend you for the cost of return postage to rule out a fault with the unit. Usually the screen goes dark (light board replacement) or it bleeds (screen replacement) - yours could be a wiring fault or a problem with the unit. PM me if interested...
Cheers
James
Cheers
James
- randall977
- Posts: 264
- Joined: Sun Jan 21, 2018 9:52 am
- Location: Oxford, UK
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Re: OBC Questions
Thanks to James for lending me his OBC. When I plugged it in it worked fine. It seems like quite a common fault that the display goes blank - I think it's the electronics in this instance. Got a used replacement on it's way, you can actually still buy them new for around £500.
Re: OBC Questions
I'm hoping I'm as lucky. Am picking up a secondhand one when back in the US later this month, along with replacement screen and LED bulbs in case its either of them. Last thing on the current to-do-list.
# 328 RHD M635csi 1986 Dinan 3.8
Jensen Interceptor Convertible 1976
Jensen Interceptor Convertible 1976
Re: OBC Questions
Anyone needing a euro OBC I have an extra one.
'84 M635csi
'86 Lotus esprit Turbo (sold)
'86 Lotus esprit Turbo (sold)