Brake light help

[whtrapta]

My passenger brake light and rear turn signal don't work. The running lights work in the back, and the front and mirror turn signals work, but flash fast. Whole driver side is normal. I checked the fuses, all are good. The wire that sends the power to make the lights get brighter for stop or turn is dead. Any one know what would cause this or how to fix it?

 

[The Car Stereo Company]

My passenger brake light and rear turn signal don't work. The running lights work in the back, and the front and mirror turn signals work, but flash fast. Whole driver side is normal. I checked the fuses, all are good. The wire that sends the power to make the lights get brighter for stop or turn is dead. Any one know what would cause this or how to fix it?

most likely you have a bad bulb in th back. a common symptom of having a bulb out is that the side turn signal flashes at twice normal speed. if its a dual filament bulb then all you have to do is replace it

 

[whtrapta]

I run led bulbs. I used a probe and there is no power coming from the wire that makes the lights brighter

 

[dataustin]

Just a guess......moisture in the 3rd Brake Light?

 

[whtrapta]

Just a guess......moisture in the 3rd Brake Light?

FROM WHAT RAIN!? but no do you think that could cause that?

 

[The Car Stereo Company]

do the led lights have a built in resistor? if so try testing the light with another 12v source just to verify the lights are working. its not often but i have seen bad circuits in led lights that caused a short in the electrical system. if the lights do work, then you would need to trace the wires back to see where the problem is.
what year truck?

 

[whtrapta]

I put resistors. They do work I tried them on the driver side and good. I really don't want to trace these wires since it's a harness and it's up under everything

 

[dataustin]

I'm not saying that's it, but I remember a thread BigJ created a while back describing all the strange issues associated with moisture in the 3rd Brake Light.

 

[BOJANGLES]

Just a guess......moisture in the 3rd Brake Light?

Whtrapta, I'm no electrical guru, but I would definitely investigate that.

I live in the bone dry desert and had moisture in my 3rd brake light that must have come from the car wash. It was back when my 2010 was still brand new. It ended up causing all kinds of hill descent control faults and other mumbo-jumbo in my instrument cluster. Took it to the dealer, they replaced some stuff up there (under warranty) and it has worked fine ever since.

It may or may not be the root of your problem, but its definitely worth a look.

 

[Squatting Dog]

Pull the third brake light, and check the circuit board for any moisture damage...

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-Greg