99 brake light and Third brake light won’t turn off

[Janson]

On my 99 my brake lights and third brake light won’t turn off. I replaced the brake switch and the wiring harness about 2 foot up due to it being Burnt Wires and melted the plug. The only way the lights turn off is if I disconnect the battery’s . Blinkers work but four-way doesn’t.

 

[B.G. Smith]

Pull up on the brake pedal, sometime the pedal does not return all the way?

 

[Janson]

I tried not much play in it

 

[Janson]

I tried that and there isn’t much play

 

[B.G. Smith]

Also some folks who live in areas where the roads are salted in the winter have had problems with corrosion in the receptacle where trailer lights plug in causing wires to short together.

 

[Janson]

I live in the top part of Texas not much corrosion. I did however disconnect my trailer brake controller and I still have the same problem

 

[Terry]

I used to do automotive/ heavy truck electrical for a living. And I would agree that the trailer connector is always suspect with a problem like this. If you unplug the brake lamp switch at the brake pedal do the lights go out? If not if you pull the 40 amp fuse # 8 in the power distribution center under the hood do the lights go out?

 

[DavidC]

Disconnecting the brake controller is not the answer, yo have to physically unplug the hitch receptacle as there is still 12vdc at that point. Apparently you have a 12vdc shorted to the brake lights and that could be anywhere from the cab to the hitch. There are also plugs in the Drivers wheel well.

 

[BigPapa]

I had this exact same issue on my ‘95. There was ONE STRAND of the “always hot” wire in the trailer connector socket that was touching the brake light wire. Don’t know how it happened. I hadn’t plugged a trailer up in weeks before it happened and I certainly hadn’t had the socket apart.

 

[Janson]

I’ll take a look at that tonight thanks.


Also last night Well I was working on the truck I found out that my blinkers and brake lights ( still stating on) only work if The hazards are In the on position. I can get the third brake light to turn off if I pull the hazard fuse

 

[GAmes]

I discovered over the weekend that if the hazard relay fails the brake lights and turn signals do not work either. Mine was easy to find because when I removed the fuse cover to check fuses the flasher was hot enough to burn me. I was expecting to have to replace the multifunction switch.