Hello all!

All of a sudden I have only one brake light. Only the left light works(so its not the pedal switch). No right side brake light or third brake light. Also, the little LEDs on the cap of the trailer harness connector that used to light up with the brakes are not lighting up. All fuses are good and no bulbs are blown. Took off right side assembly and nothing fishy looking with the trailer wiring.(it is aftermarket-came with the truck and i have never used it.) What else should I look for?

Thanks,

Aaron
2003 Disco II SE7
135,000 miles

 

Have you tried disconnecting your trailer wiring harness?

 

Unfortunately, the PO went with the splice and dice method to save a few bucks and it is not a simple matter of disconnecting the harness :-(
-aaron

 

I've seen factory wiring harness' fail causing similar issues.
Well, best way to attack this..
If you can remove the trailer connector by the receiver you should be able to
pull the harness up enough to get to the splice connectors.
Lets take a look at the wiring diagram and see if we can cut just the brake lamp wire
out of the circuit first.

 

try cutting the red or white wire..
see top of page "trailer pick up"

 

Thanks! I'll check it out when I get home from work today.

 

Well, inspected the trailer harness connector at hitch and found that it had rotted/corroded to the point of the wires not even touching once I removed the electrical tape. Removed rotted connector and installed a new 'quick tap' connnector complete with circuit-testing LEDs. All the LEDs light up now as the should with the turn signals and brake applied- BUT STILL NO THIRD BRAKE LIGHT OR RIGHT BRAKE LIGHT!

I need to figure out what is wrong.

please help.

-aaron

 

btw , i cut the red wire and the white wire at the factory connector splice and still no brake lights

 

If you have downloaded the RAVE manual, look at page 99 of the electrical diagram. Power for the brake light goes through the left brake light then to a header and splits off to the right, top, and trailer socket. The wire in question is a Green/purple wire. I'd pull both taillights, start checking power from the left,(where it works) and then follow the wiring harness until you find where the power stops, I think you'll find a broken wire or corroded connection somewhere.

 

Well, I ripped out all of the Hopkins aftermarket trailer wiring and harness and still no lights. Decided to revisit the bulbs. they looked brand new. Removed both tailight assemblies and swaped brake bulbs.....wait for it.......three days of pulling my hair out and cutting and ripping out trailer wires for nothing. Two minutes to Autozone. New tailbrake and 3rd light brake bulbs and all three brake lights are working perfectly.

Moral of the story....even if the bulbs look new with no blown filament-replace first. Ha! The fact that it was both the right brake light AND the 3rd brake light at the exact same time is waht had me convinced that it had to be more sinister than just bulbs 'cause those two are on the same circuit separate from the left bulb.

Thanks for everyones input.
Have a great rest of the day!

-aaron
2003 SE7 with fully functional brake lights!