Pressure Brake switch wiring

[LuckyLucOnBass]

View attachment 91205 Yes disconnect the yellow wire at the fuse box. Check for continuity from that wire to the frame. If you get a reading other than "I"(nfinity) disconnect the wire from the switch to the to the tail light. Then check the wire from the fuse box to the switch again. If you now get an "I" then you are good for that section. Check the wire from the switch to the light. I think you may be grounded at the fixture.

So I checked for continuity from the brake switch. It's definitely working properly. But you are right, the actual brake light fixture is grounding out at the frame. So I need to figure out how to shield the actual plate/brake-light fixture from grounding out. Plastic screws? I don't know.

 

[LuckyLucOnBass]

One thing I don't understand is why you are just blowing one not both fuses.

So since I figured out that the light fixture is grounded to the frame, why is it blowing the fuse instead of just lighting up the brake light?

OH... and I know the fixture is grounded because I checked with my multi meter. Also, I just connected the hot wire and not the ground wire. Still turned on when the key was on.

I just wanna ride this bike.

 

[weekendrider]

With the fixture bolted on can you unhook the ground wire? If so do that and see if you still have continuity to the frame. Have you had the socket apart? The fiber isolator, spring, and pigtail wires?

 

[weekendrider]

Somewhere power from the brake light wire is going to the frame is why the fuse is blowing. The pigtail wires have a clip on the bulb side it could be that clip is touching the spring that provides tension or the socket.

 

[LuckyLucOnBass]

With the fixture bolted on can you unhook the ground wire? If so do that and see if you still have continuity to the frame. Have you had the socket apart? The fiber isolator, spring, and pigtail wires?

I had to take apart the socket to resolder the ground wire. That was on a copper washer. On top of that is the spring. Then the bulb connection with the pig tails. I don't remember a fiber isolator though.

When I put one lead on the fixture and the other on the frame, I get the continuity buzz.

 

[LuckyLucOnBass]

Somewhere power from the brake light wire is going to the frame is why the fuse is blowing. The pigtail wires have a clip on the bulb side it could be that clip is touching the spring that provides tension or the socket.

On the bottom side of the bulb holder, the lead cables are shielded in a plastic fitting from touching the spring. I couldn't get a picture of that. On this light, red and black are hot, yellow is ground.

 

[weekendrider]

You might not need the ground wire then? The pig tail wires have brass clips on one end to contact the element on the bulb those usually run through a fiber or plastic washer to isolate them. like this one. Or this one.

If they used a copper washer instead of those fiber/plastic plates and the spring is touching that could your ground.

 

[weekendrider]

With the bulb out do you have continuity from the wire to the fixture? Then with the bulb in do you have continuity?

 

[LuckyLucOnBass]

You might not need the ground wire then? The pig tail wires have brass clips on one end to contact the element on the bulb those usually run through a fiber or plastic washer to isolate them. like this one. Or this one.

If they used a copper washer instead of those fiber/plastic plates and the spring is touching that could your ground.

Mine is three wires. The two, in your picture, would be my high and low beam. My ground wire is soldered to the brass ring at the base of the socket.

I added a photo of the order of pieces.

 

[LuckyLucOnBass]

This is frustrating. But I won't buy another brake light fixture. And btw, thank you all for your help!

 

[LuckyLucOnBass]

With the bulb out do you have continuity from the wire to the fixture? Then with the bulb in do you have continuity?

I have my fixture apart. I will check that tomorrow.

I'm thinking my ground wire is grounding the socket fixture. Which is what it's supposed to do. But that is grounding the bulb socket to the socket holder. Then that is grounding to the plate fixture, which is grounding to the frame. Haha. I have to stop that somewhere somehow.

 

[weekendrider]

OK I see what you are saying about the plastic tits protecting the wires. Did you try the bulb out/ bulb in tests?
Any chance that when you pull the wires back into the tits they are sticking out the bottom and hitting the copper washer?

 

[weekendrider]

If you can pull the wires out and you think there is room maybe a short piece of heat shrink around the shank of the crimped brass piece?

 

[fredintoon]

Hi Lucky,
just perhaps the Yellow ground wire being soldered to the metal ring to one side is tilting the assembly to one side and causing a short circuit?
Try melting the yellow wire off the ring, filing the ring flat and soldering the ground wire to a ring terminal that'll be trapped under one of the lamp retaining studs.

 

[LuckyLucOnBass]

OK I see what you are saying about the plastic tits protecting the wires. Did you try the bulb out/ bulb in tests?
Any chance that when you pull the wires back into the tits they are sticking out the bottom and hitting the copper washer?

Haven't tried the bulb out/in test. What would that solve so I know what to look for?

Also, the wires do not stick out from the bottom of the, uh, plastic tips. They are very well isolated. It's definitely a grounding problem.

 

[LuckyLucOnBass]

If you can pull the wires out and you think there is room maybe a short piece of heat shrink around the shank of the crimped brass piece?

I don't think it's necessary.

 

[LuckyLucOnBass]

Hi Lucky,
just perhaps the Yellow ground wire being soldered to the metal ring to one side is tilting the assembly to one side and causing a short circuit?

Is not touching any of the hot wires. I'm blowing a fuse when the lead from the brake light is connected to my brake switch. If there was a short, would my taillight fuse blow as well?
Also, grounding to the retaining screw would still ground the whole taillight /license plate fixture?

 

[Wingedwheel]

Bottom line, something is touching. Can you hook up a spare light fixture to check? Got an extra trailer light lying around? that would let you know if it's your tail light fixture...

 

[LuckyLucOnBass]

So I woke up and this happened. Nothing changed, by the way.

 

[Wingedwheel]

Crazy.......Lets hope it stays that way.