Need help with Wiring/Relay/Grounds to H1/H4's

... white wire is high beam power (thick) or indicator (also white, but thin) to the instrument panel, usually a blue light. Fogs normally go OFF when high beams are ON, that is common.
 
Mo Brighta said:
... white wire is high beam power (thick) or indicator (also white, but thin) to the instrument panel, usually a blue light. Fogs normally go OFF when high beams are ON, that is common.
Click to expand...
OK, that makes sense. I was not sure how to read the fog lamp switch. I guess what happens is if the hi-beams are on, then both sides of the the fog lamp relay coil are hot, and so it is off. If the hi-beams are off, then the residual resistance of the hi beam filaments causes current to flow in the fog lamp relay coil, and the fog lamps come on. Kind of a weird approach, but I guess it works.
 
Yeah, it's wonky but it works. The relay only takes 40 milliamps or so to work... high beams provide a workable ground path for the coil.

I think the fog light wires are grey/violet-- front - and rear fog too, if you have one. At least that's how they are in E24 and E28 cars.
 
Mo Brighta said:
Yeah, it's wonky but it works. The relay only takes 40 milliamps or so to work... high beams provide a workable ground path for the coil.

I think the fog light wires are grey/violet-- front - and rear fog too, if you have one. At least that's how they are in E24 and E28 cars.
Click to expand...
From the switch the wires are yellow/blue and grey. From the relay to the fog lamps they are yellow.
 
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