Reverse lights

[Joeyhosmanole]

Take a test light to the switch and the wires going to and from. You should be able to eliminate or confirm the whole switch area as a problem with a test light.

Thanks for your comment.

Did just that, beginning at the brake light and working forward.

Found that the brake light is the light blue wire going to the top bulb in the terminal marked "Major".

Interestingly, the tail light wires including the light blue brake light wire trace to a harness going into a TFCM near the spare tire, which is a Trailer Light and Fuel Pump Control Module.

No voltage on the light blue wire after the FTCM when the brake is pressed. But on the other side reads 12v going into the FTCM on the light blue/white wire when brake is pressed.

So I jumped a splice clamp from the light blue/white going into the FTCM directly to the light blue wire going into the "major" terminal on the top bulb on eash side bypassing the FTCM.

And boom. Brake lights now working. Tail lights, turn signals - all good.

Now need to perform a similar exercise on the reverse bulbs.

I hope this helps somebody with troubleshooting in the future.

 

[spectralen]

Nice work.
Would have cost a couple of hundred bucks for the dealer to tell you that.

 

[jmm121783]

Those trailer towing junctions are known to rust out on the insides creating a whole bunch of issues with the rear tails.....if you didn't check into that maybe replacing that will solve all the issues without having to run extra jumping wires!