I have a 1975 r90/6. The 8 amp fuse for the parking light/running light/instrument cluster keeps blowing. All the lights are functional.
I have narrowed down the problem to the following: when i remove the headlight from the bucket and replace the fuse, everything is fine and functional. I think the headlight assembly is shorting out on the bucket. Is this possible? It happens every time i put the headlight back on and is getting boring trying other things an replacing the fuse....hmm...
Any ideas? Shouldn't the bucket be ground? Why is the headlight (chrome ring...etc) "hot"?
Thanks a bunch!
1975 R90/6 75K and climbing
1977 R75/7 75K and holding
I'm no expert Rohls, but looking at the wiring diagram in my Clymer, here's what I found: the high beam circuit shares a ground with the marker light and gets power from the headlight hi/lo beam relay. Look for rubbed insulation or loose connections in those circuits. Power should only go to the bulb, not the bezel. Can you pull off the bulb holder and see any cracks or damage scorched bits? Any chance somethings getting shorted to, further in the shell? It can get pretty crowded in there.
The chrome ring should not be electrically hot, there are no wires connected to it. Does the fuse blow when the chrome ring is in place with the ignition off? Look closely for a pinched wire when the headlight is fastened in with the chrome ring.
Guy
As has been alluded to, the bucket is crowded when the headlight is in place. I would suspect that there is some unintended contact being made when the light is pushed back into the bucket. I try to make plenty of room in the snake pit of wires so the headlight connector has a clear spot to land. Sometimes, it's the same story in the fridge.
If you have an electrical tester, then see if the bezel is hot to ground when it is out of the bucket. If so, then you know the problem is right there. If not (more likely), then something inside the bucket is shorting when everything gets smooshed when you try putting the headlight into the bucket.
Thanks! it seems as though the chrome ring (/back of the light bulb housing) has the same potential as the parking light bulb.
I think the problem is limited to the headlight assembly because i change the fuse, test everything, and see a big spark ( and the fuse pops) when I place the assembly back in....right at the 'c-clip' attachment point....hmmm....
Maybe the running light wire is touching the back of the head light assembly? (there is continuity between these points....which is strange to me)....and then the short to the bucket....hmm...
Thanks again.
nick
1975 R90/6 75K and climbing
1977 R75/7 75K and holding
I had almost the exact problem several months ago with my /5. The fault was not in the bucket, but a short in a hot wire ( the rear lamp) that led to the bucket... in other words a short outside the bucket transferred the short to the bucket. Same symptoms... lights worked fine when headlamp diassembled... blew my 20 amp fuse when headlamp was re-attached with the headlight ring. Follow the wires to the bucket, the problem may be external to it.
Hank
'72 R60
'95 K75S
Rohls wrote:Hi all,
I have a 1975 r90/6. The 8 amp fuse for the parking light/running light/instrument cluster keeps blowing. All the lights are functional.
I have narrowed down the problem to the following: when i remove the headlight from the bucket and replace the fuse, everything is fine and functional. I think the headlight assembly is shorting out on the bucket. Is this possible? It happens every time i put the headlight back on and is getting boring trying other things an replacing the fuse....hmm...
Any ideas? Shouldn't the bucket be ground? Why is the headlight (chrome ring...etc) "hot"?
Thanks a bunch!
Last edited by hank0614 on Sat Oct 09, 2010 11:06 am, edited 1 time in total.
I had almost the exact problem several months ago with my /5. The fault was not in the bucket, but a short in a wire ( the rear lamp) that led to the bucket... in other words a short outside the bucket transferred the short to the bucket. Same symptoms... lights worked fine when headlamp diassembled... blew my 20 amp fuse when headlamp was re-attached with the headlight ring. Follow the wires to the bucket, the problem may be external to it.
Hank
'72 R60
'95 K75S
Rohls wrote:Hi all,
I have a 1975 r90/6. The 8 amp fuse for the parking light/running light/instrument cluster keeps blowing. All the lights are functional.
I have narrowed down the problem to the following: when i remove the headlight from the bucket and replace the fuse, everything is fine and functional. I think the headlight assembly is shorting out on the bucket. Is this possible? It happens every time i put the headlight back on and is getting boring trying other things an replacing the fuse....hmm...
Any ideas? Shouldn't the bucket be ground? Why is the headlight (chrome ring...etc) "hot"?
I had almost the exact problem several months ago with my /5. The fault was not in the bucket, but a short in a wire ( the rear lamp) that led to the bucket... in other words a short outside the bucket transferred the short to the bucket. Same symptoms... lights worked fine when headlamp diassembled... blew my 20 amp fuse when headlamp was re-attached with the headlight ring. Follow the wires to the bucket, the problem may be external to it.
Hank
'72 R60
'95 K75S
Rohls wrote:Hi all,
I have a 1975 r90/6. The 8 amp fuse for the parking light/running light/instrument cluster keeps blowing. All the lights are functional.
I have narrowed down the problem to the following: when i remove the headlight from the bucket and replace the fuse, everything is fine and functional. I think the headlight assembly is shorting out on the bucket. Is this possible? It happens every time i put the headlight back on and is getting boring trying other things an replacing the fuse....hmm...
Any ideas? Shouldn't the bucket be ground? Why is the headlight (chrome ring...etc) "hot"?
