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I had a smashed instrument cluster from a 78 R100 S. The cluster is fine, but the housing was smashed. I'm rebuilding the bike.

I replaced the housing with a 75-ish housing only to realize that the location of the Turn Signal blinker light and the Brake Failure warning light locations have been switched in the housing. So my Brake Failure light blinks when I use the blinker.

Does anybody have an idea how to swap the signal to the lights? I'm wondering what wires are the ones that send the signal to the housing to swap.
I know the black one on the turn signal relay goes to the indicator but the brake failure comes off the switch... this one has me scratching my head.
Any other ideas...

Unless anybody wants to trade a 78 housing for a 1975 housing?

My suggestion would be to un-switch the printed circuit. It would be a bit tedious but you could cut the two printed circuit pathways, then scrape the mylar off the top of the newly cut printed circuit ends, then make two jump wires with the two ends bared and then solder the wire ends to the mylar as required to get the electrons to flow where you want them to.

After making the change and verifying it, I would then cover all of the bare wires/printed circuit with some RTV silicone rubber to forestall any corrosion of bare copper or etch.

Ken

Yea, that printed circuit is a crazy road map to read. Good idea but I seriously worry about ruining it for good. I'll have another look at it and maybe test with some spare wire and see what I can re-route.

My other thought was finding what pins went to what circuit and swapping them in the plug (The rubber female side) somehow.

My other other thought was to hack into the wiring harness and swap the black/white wire with the black/brown wire but i think the lights are activated differently.

But swapping pins and wires may not be that easy. Correct me if I am wrong but the turn signal light is grounded and is activated by a positive signal.
I think the brake failure, neutral and some other lights are given a positive feed and activated by being grounded (due to the switches making a ground when activated).

JJ, here is a map of the instrument pod wiring for the 1974 /6. Yours will probably be different (but similar).



Hmm, can't get the image to show bigger. If you right-click on the image and 'Open in new tab' you can zoom in to read the text. Or if you want a hi-res PDF send me an email or PM with your email address and I'll send it by return email.

I can't see any simple way to swap the wires externally to get a solution for you since the brake fluid light is switched to +12v and the turn signal light is switched to earth. Perhaps you could just get used to your own quirky arrangement and celebrate its probable uniqueness.

Thanks Charlie,
My email is my screen name at gmail
I went and looked at everything again with a fresh set of eyes today and i'm thinking I need the proper housing... it's really the easiest solution, but also can be expensive.

Saw quite a few bare housings on ebay, all were pretty expensive. Here is a complete unit with gauges. http://www.ebay.com/itm/1978-BMW-R100-7 ... nt&vxp=mtr

Yea, thanks... The ebay hunt and the spare parts guys are on my list to call...