first wiring question

[richrd]

I'm getting ready to rewire the headlite bucket on '73 r60, trying to reconcile what the diagram says to the mess I have.

Studying the diagram, it shows the red wire feeding the main switch, but also a green / red wire from the same terminal feeding the right dimmer switch cluster.

This would mean that the diimmer switch is hot full time. What am I missing?

[schrader7032]

I could be wrong but a green wire with stripe means the power on that line will be switchable. Seems that the dimmer switch is the switch part of the circuit.

[chrishea]

There’s a few /5 wiring questions going on recently. So, for honesty’s sake, I don’t have a /5 to look at, however, when I look at the wiring diagrams in some of the other threads, the green-red wire does go to terminal 30 on the light switch, terminal 30 in Bosch/DIN wiring nomenclature does mean always “hot”, that is unswitched and unfused.

In my own research, looking at the manuals I have, it’s not clear in the Haynes manual, but is in the Clymer, the /5 headlight switch has a “push to flash” feature that activates the high beam. In the /5 wiring set-up, it does appear this is possible with the bike turned off. Back in the day when headlights weren’t required, this set-up makes more sense, with the ignition/headlight switch “down” and “straight”, the headlight relay isn’t powered, in the headlight on position, the headlight relay provides power for the lights.

The Clymer manual has two diagrams, one for early /5s without fuses and one for later /5s with fuses. It appears as though BMW changed the wire colors. In the without fuse bikes, your green-red wire is solid red, that fits better with terminal 30 always being “hot”.

Good Luck!

[richrd]

when the green/red wire goes to the same terminal (30 and 51 are the same) then that wire becomes unswitched and unfused.

I do like the way the Germans number the terminals to make it easier to know where each wire goes.

[cbclemmens]

Richard;

On the old BMWs the dimmer switch was set up so the headlight could be used as a signal lamp for Morse code with the engine off. I'm told that was for signaling submarines but there were probably other uses. Anyway there was a hot wire going to the dimmer switch. Pushing the switch down would turn the high beam on for as long as you hold it down (the flasher), center position is low beam and up is high beam, but only with the ignition on.

Craig

[cbclemmens]

Here is a wiring diagram from Haynes.

[cbclemmens]

Another wiring diagram I got from another post - reported to be from a BMW shop manual

R75-5 WIRING DIAGRAM.pdf

(248.74 KiB) Downloaded 71 times

Craig

[cbclemmens]

Try that again as a Jpeg.

Craig

[richrd]

I'll go with Craigs reply. Since there are not a lot of submarines in NW Arkansas and since I don't like unswitched voltage, I will be changing that. The British used to that. Some bikes the horn was always live and others the headlite was. So it was easy to walk away with the key in your pocket and the headlite draining the battery.

Having pulled the switch, there is a good chance I will be buying a new switch or wiring up something original.

Thanks