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F850GSA wiring color code

motodan

Active member
Have a Denali aux stop light to hook up. Which wire coding represents rear running and stop lights for the '19 F850GSA? Thanks.
 
I don't know but if it works like the F800GS then there is only one wire plus ground and the brightness is varied using Pulse Width Modulation.

Sent from my SM-G950W using Tapatalk
 
Not sure if it is the same as the F800GSA . Tail light is grey/red/yellow wire , brake light is grey/black/yellow wire and brown is ground.
 
Half success (?) hooking up aux running/stop light. Got it hooked up, turn on and aux tail light works great. Steady running light and stop light was very bright. HOWEVER, the bike's taillight didn't come on at all with TFT showing a BIG "see shop specialist /Brake fault" banner. So disconnected aux light, at which time bike's light comes on with normal stop light function. Plus no fault banner showing on TFT. The aux light was hooked up with plastic posi connectors and bike's taillight was just a three wire plug in connector. Given those simple connections have to assume the bike's computer didn't like this product. So much for extra rear lighting.

Welcome to CANBUS or whichever ZFE, PDQ, CPU or whatever doesn't want to be messed with.
 
You connected the aux light to the same wire that feeds the bike's light. Then either both have power or both have no power. That's strange!

Btw. which Denali lights are we talking about? B6? Single/dual? Where did you connect the GND wire to?

/Guenther
 
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If BMW did not made a new design there, my F700GS has only ground and ONE wire which is the brake and running light. Your connection to 'some' wire for the running light sounds suspicious to me. I would try it with only the one you think is the brake light connection and leave the other one off.

But without a diagram of the F850GSA electrics, who knows. I would contact Denali.

/Guenther
 
I can see why the B6 cannot directly be connected to bikes with pulsed brake/tail lights because it does the same thing internally. The B6 needs two simple on/off supply lines like from the CanSmart unit.

A SIMPLE LED light with two wires (+/GND) and no extra features like blinking works. It should consume less than 0.5A.

/Guenther
 
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You can tap into the license plate light wire which is going to one of the connectors in the same area.

From the B6 description the red wire is the 12V power supply. Without any power on the orange wire the B6 stays at ~50% light output. Connecting the orange wire to some power switches the B6 to 100% light output.

But the power on the bikes brake-/tail light wire is pulsed in tail light mode, 50% on 50% off. Might be enough to switch the B6 to 100% (brake!) without having applied the brakes.

Try it out!

/Guenther
 
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