bulletbill Posted May 11, 2018 Share Posted May 11, 2018 Seems I have lost power to the right low beam. Thought it was to bulb, but no. Pulled the plug to the complete Light unit looks like a common ground. with a test light I have power to all but one clip? So where do I start looking for the source to the plug for the right low beam?? Link to comment
dirtrider Posted May 14, 2018 Share Posted May 14, 2018 Seems I have lost power to the right low beam. Thought it was to bulb, but no. Pulled the plug to the complete Light unit looks like a common ground. with a test light I have power to all but one clip? So where do I start looking for the source to the plug for the right low beam?? Morning bulletbill Yes, common ground to both low beam bulbs (brown wire). 12v side has a separate power into each low beam bulb. one side is (yellow) other side is (yellow/white). Usual cause of one bulb failure is the bulb itself. (sometimes the H-7 bulb won't work in the bike but will test good remotely). The headlights in the BMW 1200RT are computer controlled so if the computer sees a high current into the bulb it will shut that circuit down. Testing remotely will still light the bulb but the computer might not like the low resistance (like a shorted filament). Other problems are the bike side terminals at the bulb burnt brown or black causing high resistance & bulb failure to work. Link to comment
bulletbill Posted May 16, 2018 Author Share Posted May 16, 2018 dirtrider, Thanks for the reply, this happen as I was leaving on a Road trip, will be back next week to continue checking, we changed the bulb and discovered that it didn't fix. Link to comment
dirtrider Posted May 16, 2018 Share Posted May 16, 2018 dirtrider, Thanks for the reply, this happen as I was leaving on a Road trip, will be back next week to continue checking, we changed the bulb and discovered that it didn't fix. Morning bulletbill Was the new bulb verified good (maybe a defective bulb)? Did it come on at all? Certain H-7 bulb types you can't touch the glass part of the bulb with your fingers or the bulb could crack shortly after first lighting. Is something tied into the 12v power going to the headlight side that is out? Some use one of the headlight power wires to trigger an underseat fuse box or relay for other accessories. If that is the case & that circuit is shorted to ground then the computer can shut that side headlight off. Link to comment
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now