MOTOBRICK.COM

TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: bluto359 on July 21, 2017, 08:32:32 PM

Title: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 21, 2017, 08:32:32 PM
I've had this bike a couple of years now. There's a switch between the key switch and the hazard switch, it has a brown wire and a yellow/violet wire into it. The symbol on the indicator is missing. It has power to it and does continue when it's flipped but I have no idea what it's for. Heated grips? Every diagram I find doesn't show it. Before I tear off the tank again, does any one Know what it's controlling?
Title: Re: K75s 1987 switch between key and hazard?
Post by: Scott_ on July 21, 2017, 09:53:18 PM
Does your bike have ABS on it.
Your wire colors don't match the ABS diagrams I have(brown and black), but brown in usually ground on these bikes.
A heated grip switch would be 3 wires, not 2.

The diagram I have shows 3 wires to the Hazard switch, Blue/White, Yellow/Violet, and Brown.
Title: Re: K75s 1987 switch between key and hazard?
Post by: rbm on July 21, 2017, 10:11:45 PM
It's the hazard switch you have identified.  The Blue/white wire is included on those switches which have an integrated lamp and will flash in unison with the indicators.  If you don't have the Blue/White wire, the hazards will still work.
Title: Re: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 23, 2017, 03:17:05 AM
I have a hazard switch and it works fine. The switch in question is between the hazard & key switch, looks oem also, has only 2 wires, has battery voltage when key is on. It does continue voltage when operated but I don't see anything working when it is. I suppose I could see if it flows any amps. Just curious to see if anyone knows for sure what else it could be.
Title: Re: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 23, 2017, 03:17:45 AM
Does not have ABS.
Title: Re: K75s 1987 switch between key and hazard?
Post by: Laitch on July 23, 2017, 06:42:54 AM
The wiring will need to be traced. It might have been for aftermarket lights, for grip heaters, to test the cooling van, or even for activating high altitude fuel adjustment if the bike were previously used at elevations that might have needed that.

Maybe it had Magic Fingers massage in a previous seat. There's just no telling.
Title: Re: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 23, 2017, 11:35:26 AM
It's surely an oem switch, it might be an add on. I'll run it down. Does anyone know of a switch, oem or not, that will drop into the switch pad? I have a couple of led lights, low amp, that I want to add and there's an empty space in the switch housing. Anyway, thanks for trying, :2thumbup:
Title: Re: K75s 1987 switch between key and hazard?
Post by: rbm on July 23, 2017, 11:59:15 AM
The switches used by BMW are pretty much standard marine grade rocker switches, available from a variety of manufacturers.  One good manufacturer is Carling Switches, the Contura 2 (http://www.carlingtech.com/rocker-switches-sealed) series.  These are sold by Eastern Beaver (http://easternbeaver.com/Main/Elec__Products/Switches/switches.html) amongst others.  Check out a local marine supply shop using the dimensioned drawings provided at that link.
Title: Re: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 23, 2017, 12:17:16 PM
Cool, thanks! Got one ordered. :2thumbup:
Title: Re: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 23, 2017, 02:08:30 PM
Found it. Plugs into the jetronic harness, turns into GRN/RD & BLK wires. Looks like its for altitude. I guess it take place of a BAP sensor?
Title: Re: K75s 1987 switch between key and hazard?
Post by: bluto359 on July 23, 2017, 02:16:30 PM
LHS frame by air filter box. Manual say 4000' or higher. I doubt I'll ever see that on this bike but stranger things have happened.  Thanks!!