headlight relay/wiring question
05-22-2007, 10:39 PM
#1
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headlight relay/wiring question
I fired my old headlight relay months ago and finally got around to installing the one I bought from Stan.
The headlight combination relay (at least the one for pre87 cars) is three relays in one case. Two relays are near the CE panel and one is farther back. The one far from the CE panel 'activates' the functions of the relay. Wrapping a rubber band around this relay to close it would make my headlights work, but they wouldn't turn off with the ignition or when the switch retracted them.
The new relay works perfectly... except it will not put the headlights down. They go up. They turn on. They turn off. They just don't go down. Since the old relay lifts and retracts the headlights, the limit switches must work fine.
I have figured out most of the wiring diagram of the relay, except for how the relay determines what to do with the motor. Can anybody provide some insight?
Pins:
bM30 limit switch 12V?
b30 headlight switch off
X instrument/ashtray/lighter
56 headlight switch on II
a30 12V in from motor fuse
30 12V
31 12v wiper/washer/etc
M86 limit switch ground?
M30 12V out to motor
86 high/low switch
a56 high beams
b56 low beams
The headlight combination relay (at least the one for pre87 cars) is three relays in one case. Two relays are near the CE panel and one is farther back. The one far from the CE panel 'activates' the functions of the relay. Wrapping a rubber band around this relay to close it would make my headlights work, but they wouldn't turn off with the ignition or when the switch retracted them.
The new relay works perfectly... except it will not put the headlights down. They go up. They turn on. They turn off. They just don't go down. Since the old relay lifts and retracts the headlights, the limit switches must work fine.
I have figured out most of the wiring diagram of the relay, except for how the relay determines what to do with the motor. Can anybody provide some insight?
Pins:
bM30 limit switch 12V?
b30 headlight switch off
X instrument/ashtray/lighter
56 headlight switch on II
a30 12V in from motor fuse
30 12V
31 12v wiper/washer/etc
M86 limit switch ground?
M30 12V out to motor
86 high/low switch
a56 high beams
b56 low beams
05-23-2007, 03:39 AM
#2
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The limit switches inside the motor are obvioulsy telling relay they are down truly, but not making circuit for lowering when up. I would check the relay socket first for good contacts, then check the 4 wire connectors up by the headlight motor for making good contact....noting where each goes before dismantling. If that doesnt help , if you can work out how, you might be able to simulate the limits working by shorting two leads together or earthing one...When my relay failed, I tried cleaning the contacts, verifying the leads were ok, and that the limits were clean, before fitting a new relay, which solved all the problems...
jp 83 Euro S AT 50k.
jp 83 Euro S AT 50k.
05-23-2007, 09:16 AM
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Originally Posted by jpitman2
When my relay failed, I tried cleaning the contacts, verifying the leads were ok, and that the limits were clean, before fitting a new relay, which solved all the problems...
jp 83 Euro S AT 50k.
jp 83 Euro S AT 50k.
05-23-2007, 12:43 PM
#4
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Matt,
Do you have the right relay? The 87+ relay works differently from the <87 relay?
It could also be one of your diodes in the limit feedback switch is fried... (on the motor).
Alan
Do you have the right relay? The 87+ relay works differently from the <87 relay?
It could also be one of your diodes in the limit feedback switch is fried... (on the motor).
Alan
05-23-2007, 04:37 PM
#5
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I went out to play with it and it worked fine. Took it to get inspected and it failed. 
It was only 1 of the (nitpicking) failure points, but still disappointing.
It was only 1 of the (nitpicking) failure points, but still disappointing.
