Electrical issue - headlight fuse is dead

[John Hopkins]

Originally Posted by rb608

Hmm. That sounds easy enough, but why would the headlight wiring run through there?

the supply to the fuse runs through the ignition switch but so does the fan, brake light,horn, and other bits..

Check the fuse by setting the meter to about 20v dc and with the ignition switch on, put the negative lead of your meter to the negative pole of your battery then touch each side of the fuse and expect 12v dc..then check all the other fuses..If you have 0v on both sides of ONLY the headlight fuse the fault is a poor connection on the back of the fuse box..

The first step of electrical fault finding is to check for dc volts across the battery..then check that the leads are tight on the battery then check that you have the same voltage from the positive pole of the battery to ground (frame) because the negative pole of the battery is tied to the frame..

John.

[SpoonMan]

I forgot about that stupid switch. Especially with the cold and maybe you just washed it? Sometimes just needs cleaning and a little di-electric grease.

[rb608]

Originally Posted by John Hopkins

Check the fuse by setting the meter to about 20v dc and with the ignition switch on, put the negative lead of your meter to the negative pole of your battery then touch each side of the fuse and expect 12v dc..then check all the other fuses..If you have 0v on both sides of ONLY the headlight fuse the fault is a poor connection on the back of the fuse box..
John.

Yep, that's exactly what I have - 12v across every other fuse except the headlight fuse; but I didn't check from the batter neg, only across the fuse connections.

Man, I took another look at that fuse box this morning. I don't know how I'm going to get inside there.

[John Hopkins]

Originally Posted by rb608

Yep, that's exactly what I have - 12v across every other fuse except the headlight fuse; but I didn't check from the batter neg, only across the fuse connections.

Man, I took another look at that fuse box this morning. I don't know how I'm going to get inside there.

Ok now check as I said because if you have an open circuit after the fuse there will be no potential difference across the fuse..

don't make it hard for yourself by trying shortcuts..

John.

[rb608]

Originally Posted by John Hopkins

don't make it hard for yourself by trying shortcuts..

It was dark. I was cold. I was getting aggravated. At least I knew when it was time to put.the voltmeter.down. and go get a drink. We'll try again tonight, thx.

[jpr1968]

There is contact in the start button to disable the headlight as you are starting it so the headlight doesn't drain the battery. Since you have running lights and a headlight the contacts could have burned through. If the Aux lights were wired in the same circuit as the headlight it is too much current for the start switch. Aux lights shouls alwasy be powered directly from the battery through a relay that is triggered by the headlight.

[Scrapdog2grand]

As John said. you have to use a good ground when checking for voltage at the fuse, if you have voltage then you go to the Start switch, if good there you go to the dimmer hi/lo switch and anything else that may be in between the 2 of the switches, a connector perhaps.

[John Hopkins]

Originally Posted by Scrapdog2grand

As John said. you have to use a good ground when checking for voltage at the fuse, if you have voltage then you go to the Start switch, if good there you go to the dimmer hi/lo switch and anything else that may be in between the 2 of the switches, a connector perhaps.

Sorry but that is wrong..If you have voltage at the fuse it has already come from the battery to the ignition switch and on to the fuse..

All I ask is that if you do the things I say and then tell me the results I will tell you what to do next..I can't test it for you myself because my arms aren't long enough to reach..

To the person who said the ignition switch could be faulty..that is true but the bike is only 13 years old if I understand correctly and the contacts usually last for at least 25 years..However if there is no voltage at the fuse that will be the next step and the contacts can be repaired..

Because of the strange method of testing the fuses we will just have to wait and see..

John.

[Scrapdog2grand]

Originally Posted by John Hopkins

Sorry but that is wrong..If you have voltage at the fuse it has already come from the battery to the ignition switch and on to the fuse..

All I ask is that if you do the things I say and then tell me the results I will tell you what to do next..I can't test it for you myself because my arms aren't long enough to reach..

To the person who said the ignition switch could be faulty..that is true but the bike is only 13 years old if I understand correctly and the contacts usually last for at least 25 years..However if there is no voltage at the fuse that will be the next step and the contacts can be repaired..

Because of the strange method of testing the fuses we will just have to wait and see..

John.

Not the ignition switch John , the start button on the right side of the bar. if he has power at the other fuses the ignition is good.

[John Hopkins]

Originally Posted by Scrapdog2grand

Not the ignition switch John , the start button on the right side of the bar. if he has power at the other fuses the ignition is good.

Ahh yes I can see where you are going, the black and red wire goes from the fuse goes to the start button and the kill switch, then it goes down to the overcomplicated and undernamed turn sig switch where it finally changes from a blue white wire to a blue wire before completing its journey to the headlight..A short in that switch or the turn sig switch or loom would blow the headlight fuse..But I am getting ahead of myself the fuse may not have blown, this could all be down to a poor headlight connection or even a blown bulb..

John.