Headlight, tail light, and running lights misbehaving

[bob21]

Greetings,

I have a 2002 GZ250 that has recently developed some electrical problems.

First, the headlight stopped working. Good bulb, good fuses, clean contacts in the hi/lo beam switch. I tested each visually and with an ohm meter.

Then it worked again, but the tail light and running lights stopped working. The brake light still works, and the turn signals work perfectly. The bulbs and fuses are all good, tested visually and with an ohm meter.

At the fuse-box, testing for DC across the fuse terminals, I have full voltage going to the taillight, which makes sense because the brake works. The wiring from the fuse box to the tail light assembly looks intact and the contacts I have identified are all clean.

But the voltage to the headlight fuses is very low (when the headlight is not working. It still works occasionally).

I also checked the kill switch and starter switch - they looked fine. The clutch and side stand switches are working properly. The bike runs great. Just no head, tail, or running lights!

Someone suggested it may be the ignition switch, so I replaced it with an Emgo ignition switch - no dice.

Just finished a short ride at the start the headlight was out. After ~5 minutes it came on!

What am I missing?

[blaine]

Bad main ground??

[alantf]

Yes - sounds like a wiring fault. Perhaps a break that keeps making and breaking. If I were you, I'd physically check the wiring from front to back.

[GilHirien]

I am having a similar issue, so I'll piggyback on here for now in hopes that it might help us both find a solution. I have headlights, but no running lights at the front turn signals (turn signals work, but possibly weakly) no lights in the speedo housing (bulbs work, tested in the highbeam indicator socket and came on when appropriate), and no tail light. Brake light also works without issue. I have traced nearly all of the harness and have not found a problem that jumps out at me yet. Had a potential fault in the headlamp bucket but fixed that up and still having the same problem.

[GilHirien]

Ok, so I won't be much help then afterall. I went and checked my engine ground and tinkered some more to no avail. Then I decided in sheer frustration to check fuses again. I had a blown tail light fuse which was the cause of all my problems. I checked it before, but not that closely and it was getting dark, but in the light I saw the break. Replaced it and I'm good to go. Sorry I wasn't much help with the original poster's problem.

[alantf]

Your answer is more correct than you might imagine. A blown fuse is exactly the same as a break in the cable (except that the break is where it should be, and not in the wiring harness)

[Water Warrior 2]

Originally Posted by GilHirien

Ok, so I won't be much help then afterall. I went and checked my engine ground and tinkered some more to no avail. Then I decided in sheer frustration to check fuses again. I had a blown tail light fuse which was the cause of all my problems. I checked it before, but not that closely and it was getting dark, but in the light I saw the break. Replaced it and I'm good to go. Sorry I wasn't much help with the original poster's problem.

Checking the fuse with a meter is best. A visual check can fool you. Remove the fuse and test it to be assured it is good.

[raul10141964]

check the connection inside the head light the part when the wires flex when you turn the handler bar

[Water Warrior 2]

Originally Posted by raul10141964

check the connection inside the head light the part when the wires flex when you turn the handler bar

Yup, check the wiring around the steering head and the wiring in the headlight bucket. There is quite a bit of vibration in the headlight to cause wear on the wiring. The wiring at the steering head gets a lot of pulling and pushing with the flexing it goes through as you turn the bars. All it would take is a partial break in a wire to cause a lot of grief. Make sure the wiring is free of hang ups when the bars are turned. This is about the only place on the bike that you don't want secure unmovable wiring.