Under dash wiring identification

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randall977
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Under dash wiring identification

Post by randall977 »

I'm trying to get my fog lights working and suspect the problem is under the dash. Can anyone help me identify these loose wires?

A coupe of questions;

Does the fog light switch appear to be wired correctly - hard to tell the faded sticker colours? Is 'A' fog light related?

Why does the cabin temp sensor 'D' have three wires going in but only two live connections on the sensor?

I can't find the connection for the chimes - may have been snipped - could it be some of 'C'?

Wire 'B' goes into the A-post but I don't think it should...

Thanks for any help - I have been studying the wiring diagram...

Dash-Wiring.jpg
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baders
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Re: Under dash wiring identification

Post by baders »

A = does not correspond to fog light switch wiring.
B = ??
C = ??
D = Brown is ground. Green/yellow is 12v + from the AC selector switch. Blue is temp sensor input to the heater regulator.

Fog light switch wiring should be grey/red and grey. Note this is for a 1986 635csi. You have not specified your model.
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randall977
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Re: Under dash wiring identification

Post by randall977 »

Thanks for the reply Baders - it's a late 82 model - series 2. I think that two of the 'C' wires are speaker wires.
rhanley 635csi89
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Under dash wiring identification

Post by rhanley 635csi89 »

The fog lights on US cars only work when the head lights are on, hopefully it's this simple. Ask me how I know, I spend hrs working on mine and then a friend told me "turn the lights on".
Our member Song was have the same issue, that was the problem.
Roger

Edit: Euro cars have a different switch as there are rear fogs in the euro models.
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randall977
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Re: Under dash wiring identification

Post by randall977 »

Thanks for the reply - no didn't get caught out by that one!

As far as I can tell the Grey wire on the fog light switch should be getting 12v from the light switch when turned on - it's only getting 0.4v... The Red and White wire is getting 12v constantly but I'm sure this should be 0 until you switch the lights on and then it activates the fog light relay? Faulty light switch? Dodgy wiring in the fuse box...more testing to follow...

Also the headlight dash lights don't illuminate when the lights are on - bulbs are fine, relays work...?

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randall977
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Re: Under dash wiring identification

Post by randall977 »

Well I sorted out my various wires. The red and purple wires were back to front on the fog light switch - faded colours mislead me. The fogs have independent supplies under the headlights so the E23 loom I added which splits one supply wasn't helpful. There are no headlight lamps on the cluster - only for fogs and full beam. Purple wires 'C' are speakers...
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