Brake light problem

[SlicksInRain]

The right brake light seems to be a problem on my 1990 Chevrolet K5 Blazer. Sometimes there will be no light at all and now the tail-light works, but the brake light doesn't. It will stay lit, but will not get any brighter when I tap the brake petal while the drivers side will light up.

I know this from looking at the reflection of light off the garage wall when I was backing it in. Also my friend was following me one day and said no brake lights were working at all, just the tail-lights. One brake light came back and the other still goes on and off. Sometimes all together too, not just for braking purposes.

What is lose or needs to be replaced?

Thanks in advance guys.

 

[lectric80]

Start by checking the wiring under the truck. Right side brake light is a dark green wire. It is very common for it to be corroded or otherwise broken, especially if there has ever been trailer lights hooked up.

The light green is the backup lights, yellow is the left side brake/turn.

 

[SlicksInRain]

U-Haul did hook up a trailer kit for it a while ago.

Should I go back to them?

I don't recall this problem happening until after the "hookup".

 

[lectric80]

I would bet they used scotchlocks on it, and they are notorious for cutting the wire and causing all kinds of havoc. If it is recent, take it back to them to fix the issue, but double check it first. My guess is you will have a splice that is corroded and has broken the connection. If it wasn't caused by the installation of the trailer wiring, I would be very surprised.