To put it simply: My 3rd brake light doesnt work and the volt meter shows nothing when the brakes/reverse is applied. What would yall have me check first?

 

You check the fuse for it?

 

all the fuses seem to be ok. im gonna look in the manual for it though.

 

the only fuse I could find was one that was labeled reverse lamps. To be clear, all the other lights work. there just isnt any power going to the 3rd brake light. does anyone know where i could trace the wires to to see if it is even plugged in?

 

They are run up above the headliner. and down the door post on the driver side.

 

where do they end? would i be able to see them in the engine bay?

 

They run down the door post and under the carpet. Then they run under the dash and into another wiring harness. I don't think you can find them under the hood.

 

there is a wire that does from your brake switch to to the third brake light. atleast thats how my 02 is. another wire, light green if i remember right runs from the switch to the multiswitch blinker thing then to your brakelights. if i remember right. or maybe both run through the blinker stalk. if its not a fuse or bulb check those connections

 

You might pull the light from the back of the cab and peer in through the hole. To get at much of the wiring, you will have to drop the headliner. The wiring for dome light and third brake lights end up under the carpet under the driver's seat.

 

darn. looks like i might actually have to try hard to get it to work, lol

 

Worse comes to worse, drop a new wire down the inside of the cab, down under the frame rail and tie into the tail lights.

BTW, what does your 3rd brake light have to do with your reverse lights? Did you wire the cargo lights to go on with your reverse lights?

 

Say what? I thought that the 2 white lights on the light were for reverse. What is this "cargo light" you speak of?

 

The 2 white lights on the side of the 3rd brake light are Cargo lights. They turn on when you open your door or turn on your interior lights. Some trucks do not have this and the whole light is red.