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Legend headlight fuse keeps blowing

3K views 5 replies 5 participants last post by  sandblaster 
#1 ·
So, my girl and I took the Legend to Americade this weekend and all was going well until I noticed the tach. had dropped to zero. I then noticed I had no horn no, neutral indicator or high beams. I bike was still driving fine and the cooling fan was kicking on in the traffic so I drove on through until we got to our destination.

I pulled the headlamp fuse and noticed it had blown. After replacing it everything worked just fine. I drove around a little bite and it blew again. I bought some more fuses. Each time I would plug one in and start the bike everything would work just fine then at some random point it would blow. Putting it in gear would make it blow or drive around a little while and all would be fine, high beam, low beam, brake, rev the engine, hit the horn, hit some bumps in the road and it still worked just fine then suddenly it’ll just go. We ended up comming home today with no headlight which was a little disconcerting.

Has anyone experienced this before? Got any ideas about where to begin troubleshooting?

Thanks for the imput!


[ This message was edited by: RideVT on 2007-06-10 15:44 ]
 
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#2 ·
YAY! I finally get to help here...I had the same issue on my '01 Legend. The problem is occurring in the headlight wire harness, at least it was on mine. Took me forever to find it, but I did. After many wheelies, I discovered that I had rubbed the insulation off of a few wires, and they were grounding out on the headlight chassis. Check it out and lemme know!

Poke
 
#4 ·
Hello

i had the same problem at my TB with the taillight fuse.
I have searched 2 days, in the wiring harness in the headlight.
Then i noticed that one cable has a little whole in the insulation just after the plug, only 1mm big, hard to see.

Good luck

dynam
 
#5 ·
Yeah, these problems can be very hard to find, especially when the ground only appears when vibration brings it in contact with a metal part. A volt/ohm meter can be useful, but often isn't.

Does it happen irregularly, or after the same amount of time since the fuse blew last? Is it more frequent in hot weather?

A fuse can carry just a little too much current for a while before it blows. It blows when it's too hot (hopefully from the current passing through it, but it's possible that very hot weather can cause the fuse to blow sooner) . If there doesn't seem to be any rhyme or reason to the fault, it's probably an intermittant ground short circuiting the "hot" wire to ground, which will blow the fuse with a quickness and a little 'pop'. Sometimes looking at the fuse can show the difference between a sudden blow vice a gradual melt - if you have black marks on the inside of the plastic window, you probably have a intermittant ground.

If you suspect a slight overcurrent and have a battery charger, you might try leaving the ignition on (so the headlight is lit) and the engine off for a while and see if the fuse blows. Not so long that the headlight becomes dim, or you may damage the battery. Don't leave the battery discharged overnight or longer, or it might stay that way. If the fuse blows with no vibration, you might have a problem with one of the components supplied by that fuse drawing too much current. This type of fault is not likely at all, but it's easy to check for.

If it indicates a intermittant fault (much more likely), you might try wiggling the suspect wires with the headlight on to try to simulate the vibration causing the problem. This can be hard to do, because many spots (like inside the headlight nacelle) are inaccessable to wiggle.

When I get a persistant intermittant ground like this, I figure out (from wiring diagrams) where the fault could possibly be, then clean the wires carefully with isopropyl alcohol (no residue) or WD-40 (doesn't harm wires or conduct electricity) and then inspect them under a *bright* light. Look for shinyness (copper showing) and for wear scars in insulation. A .1mm cut in the insulation might not be visible under normal garage lighting. I know that this isn't always possible without major dissassembly and cutting of insulation tubing, so look for the problem in the most accessable and likely spots first. An effective repair can be as simple a matter as wrapping a few layers of electrical tape around the cut, but try not to do this if the wires are likely to get wet or dirty - electrical tape adhesive can attract dust and bring the problem back.

Hope this wasn't too long and that it was helpful.
 
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