fuse blows

[dan monday]

Every time I touch the brakes my fuse blows. Why is this ?

[Trader]

My guess would be a worn wire .

 

I know....don't thank me

[ragtop69gs]

It's a 1st Gen, their supposed to do that

[Brake Pad]

are you keys hanging down and touching something?

[GeorgeS]

First pull out both brake light bulbs, and inspect the bulb sockets. Might be a short there.

Also, replace both the bulbs its possible for the bulb to be shorted internally.

 

I assume fuse blows with either handle bar,or foot brake, if so, then there might be a shorted to ground wire between the brake light relay and the two bulb sockets.

 

Remove bults, the find the relay, unplug the relay, then start checking the wire from relay running back to the bulbs, might be a short to ground on that wire.

 

Under the passenger seat. on right side, find the large plug with about 15 wires going thru it, clean that plug, might be the trouble spot.

 

Start with the bulbs, and sockets, look for problem there. e

[frankd]

Dan,

 

Either you have a wire that has the insulation worn and is touching the frame, a brake light socket that has fallen apart, OR if you're lucky a shorted brake light lamp itself. The first thing to do would be to remove both brake lights and look at the filaments. IF they're both OK, leave them out for now. Then take the seat off and inspect the wiring harness. Next unplug the tailight. Then unplug the fork anti dive solenoids. 2 other possibilities are that one of your brake switches has fallen apart or the anti dive solenoid relay has a shorted coil (unlikely). Does you bike have any added brake lights? If so, this wiring would likely be the problem

 

Doing all these tests is going to blow a lot of fuses. To avoid this, you can take an old car headlight, and connect jumpers to 2 of the pins. Touch the jumper leads to the positive and negative battery terminals (car or motorcycle) and verify that the headlight lights bright. If it lights dim, move one of the jumpers on the headlight to the other terminal. Then connect the jumpers to both fuse terminals (no fuse installed). What the headlight will do is 1)light when a lot of current is flowing and you can tell that the fuse would blow if it was installed. 2)Limit the current (no damage). 3) Save a lot of fuses and money.

[Trader]

Dan,

 

Doing all these tests is going to blow a lot of fuses. To avoid this, you can take an old car headlight, and connect jumpers to 2 of the pins. Touch the jumper leads to the positive and negative battery terminals (car or motorcycle) and verify that the headlight lights bright. If it lights dim, move one of the jumpers on the headlight to the other terminal. Then connect the jumpers to both fuse terminals (no fuse installed). What the headlight will do is 1)light when a lot of current is flowing and you can tell that the fuse would blow if it was installed. 2)Limit the current (no damage). 3) Save a lot of fuses and money.

 

That seems like a great idea for troubleshooting...but how can you tell the difference between a good circuit and a bad circuit? Will the headlight be noticeably brighter (when the fuse would blow) than normal? Or would it only light if an excess current is present?

[Flyinfool]

Doing all these tests is going to blow a lot of fuses. To avoid this, you can take an old car headlight, and connect jumpers to 2 of the pins. Touch the jumper leads to the positive and negative battery terminals (car or motorcycle) and verify that the headlight lights bright. If it lights dim, move one of the jumpers on the headlight to the other terminal. Then connect the jumpers to both fuse terminals (no fuse installed). What the headlight will do is 1)light when a lot of current is flowing and you can tell that the fuse would blow if it was installed. 2)Limit the current (no damage). 3) Save a lot of fuses and money.

 

 

 

You can also go to a local auto parts store and get a resettable circuit breaker that will fit the fuse clips. This way you just keep pushing the button till you find the problem. once it is fixed, put a fuse back in.

[dacheedah]

The reset breaker is a good idea, If you pull the bulb and try it and it trips, it tells you it's upstream of the fixture. I would start at the rear and go forward tracing your line looking for chaffing or connectors.

Has the fuse box been replaced or are you using the glass fuses? Lots of gremlins come from the old box. My experience has been intermittent issues are usually ground and blown fuse is usually the positive.

[frankd]

If you take the tail lamps out and disconnect the anti dive solenoids, the only thing you have left (I think) that normally draws current is the anti dive relay, and it shouldn't draw very much current. For the headlight to light brightly you will have at least 5 amps flowing. If the headlight glows bright, you still have a short circuit. To give you an idea of what the headlight will do, connect it accross the fuse before you disconnect anything OR pull the tail lights. Because you know it would blow the fuse, the headlight will come on bright when you step on the brakes. Now start disconnecting things, and when you get to a point that the headlight doesn't glow bright when you step on the brakes, you will know what's causing your problem.

 

Frank D.