R90S Wiring issues - extra wires

[trweber]

I am wiring my 1975 R90s and I hope I never have to do this again. Most items seem to work correctly but the following:

The brake light comes on when I turn the key on but goes off when I press the rear brake switch.
The headlight does not go on with the key but the flasher switch will make it light up.
In the headlight I have 2 wires that I have no idea where they go. One is a green/red wire that I know it is part of the brake light. Just not sure what to do with it. The other is a yellow/white wire (thicker). It seems to be a ground.

Can anyone tell me where these wire go or point me to some pictures?
Thanks for your help.
Todd

UPDATE:
My eyes hurt looking at the wiring diagrams..

I solved the issue with the yellow/white wire. It went into a relay.
The green/red wire still doesn't have a place to go.
I think the brake light issue may be tied to working on the brake master cylinder. I don't have fluid in the reservoir yet. What do you think?

 

[20774]

How good are you at circuit diagrams? You should probably spend some time confirming what you have. Here's one on Snowbum's site:

https://bmwmotorcycletech.info/schematic1975,1976.htm

Here's another one:

https://vdocuments.mx/bmw-r606-r756-r906-r90s-wiring-diagram.html

Probably should have your Haynes manual so you bounce all of them off each other!!

 

[stevenrankin]

Green Red

From what I can see on the wiring diagrams, the green/red wire is your brake light hot wire. I have it showing attachment to both the front brake switch and the rear brake switch. St.

 

[stevenrankin]

Green/red wire

I forgot to ask, just where is the loose green/red wire at? is it in the headlight shell?

As one who has fat fingers and bifocals, I find it VERY difficult to work in the confines of the headlight housing where most of the wires tie in to the colored board.

Anytime I see someone having an issue where they have just rewired replaced or restored a bike which may have involved plugging or unplugging wires from the color coded board inside the housing I suggest, they recheck their work. It is very easy to get a wire plugged into the wrong spot.

So in this case, IF, you have had the front switch assembly off the bike or have changed it, There is a possibility the green wire, might just be plugged into the wrong spot, or, it might just plug into the board and you can't see the Green/red spot.

Do you get my drift? St.