Taillight Harness Removal

[bmcgc]

My new taillights arrived and it is not going to be a simple P-N-P swap.

I removed about 12 feet of wire and numerous wire taps that used to be a 4-pin trailer plug from the harness where it goes under the tub to the taillights.

The passenger side brake light does not work and the turn signal flashes fast. I have checked and replaced all lamps.

I am unable to pull the passenger side wire out far enough to unplug the light, it seems the harness is binding on something, the driver side has enough slack in it.

I need to pull the taillight harness into the tub for inspection and repair. Not sure why there is an extra lamp wired in the driver light housing.

How difficult will that be? I do not see any wiring under the jeep, is it covered or under splash shields?

I also have some harness issues in the harness just behind the driver seat that will need to addressed. It looks like part of a tow harness was spliced in.

Appreciate any assistance figuring this out.

 

[TJ Jim]

Dang what a mess. I’m thinking I pulled the wheel well cover which made it a bit easier. Thirteen Christmas tree push pins which you can buy on Amazon. Maybe just seven. Depending on your year you might have a gas recirculating box in there. I don’t even see the stock wiring harness there in the grommet on the drivers side in your pics. Your gonna have to pull out the wiring schematic and get it wired correctly.

 

[macleanflood]

The "easiest" way to get the entire harness out is drop the gas tank. The harness ends at the passenger side, drops down, runs just under and near the lip of the skid, and then back up on the driver's side, into the tub where it follows the driver side to just under the dash where it terminates into the big block of connectors.

You probably could just unbolt the back of the tank and lower it down 2-3 inches.

-Mac

 

[Moglocker]

The "easiest" way to get the entire harness out is drop the gas tank. The harness ends at the passenger side, drops down, runs just under and near the lip of the skid, and then back up on the driver's side, into the tub where it follows the driver side to just under the dash where it terminates into the big block of connectors.

You probably could just unbolt the back of the tank and lower it down 2-3 inches.

-Mac

Is the Jeep rusty?I bought a dodge plow truck one time that had those strobes like that,or maybe it was a security vehicle.yes I would rework or replace that harness,are they like that on the front signals also?

 

[bmcgc]

Nothing is easy...

 

[Stinkbug]

Often extra bulbs are placed in the housing for flat towing the Jeep behind a RV or truck.. By adding a second bulb, it eliminates the need to have a set of magnetic lights or tapping into the existing harness and having to use diodes.

 

[macleanflood]

Nothing is easy...

In comparison TJs are easy.

My father in law and I have been troubleshooting the headlights or lack thereof on his 2011 Ford Fusion. Work fine on brights... nothing in normal. Bulbs are fine. Fuses are fine. We're deep into checking can bus relays and everything...worse is this Fusion was made for two years with completely different wiring...so a super complicated one year only.

I tub and frame swapped my Jeep in eight days and drove it on a 1600 mile road trip.

Or I spent the last eight days trying to turn on a headlight.

-Mac

 

[Moglocker]

Often extra bulbs are placed in the housing for flat towing the Jeep behind a RV or truck.. By adding a second bulb, it eliminates the need to have a set of magnetic lights or tapping into the existing harness and having to use diodes.

Often extra bulbs are placed in the housing for flat towing the Jeep behind a RV or truck.. By adding a second bulb, it eliminates the need to have a set of magnetic lights or tapping into the existing harness and having to use diodes.

That’s most likely what it was,if that’s the case the original harness should be unmodified.

 

[bmcgc]

Looking at this pic behind the driver seat, there is a wire tap and what's left of a trailer tow harness.

I suspect that this was towed behind a MH, but I see no evidence that a baseplate was bolted to the front.

 

[Stinkbug]

I suspect that this was towed behind a MH, but I see no evidence that a baseplate was bolted to the front.

Not that it is relevant to your current project, but many of us flat tow using the bumper recovery points eliminating the need for a traditional baseplate.

 

[Mike_H]

What year? Sometimes, the harness is trapped by the evap system and charcoal system (on 03 and up models). Its fairly simple to remove that enough to get to the harness and free it up (5 bolts). Three are SUPER easy to find, once you remove the wheel well liners. The 4th becomes apparent immediately after pulling te first three (technically, 2 bolts and a nut). The fifth is kind of a bugger. Its a vertical bolt, and its kinda hidden between the tub and the charcoal canister. You just have to loosen it (open slot in the bracket) but you have to know its there to get the emissions stuff free.

 

[bmcgc]

My TJ is a 99.

I can pull the passenger side light out about 4 inches, not enough to get to the connector.

I dropped a bore scope down the hole this morning but couldn't see anything.

I have removed all the wiring that used to be for a trailer. The 4 wire trailer harness was spliced in the factory harness behind the rear seat, run through the tub conduit, more splices at the rear of the tub and dropped down into the wheel well and then I have no idea what was done from there. The four prong plug on the tow hitch was not attached to anything.

Other than some bare wire from the splicing, the tub harness looks to be intact. I can tape the bare wires up.

All the exterior lights work except for the right turn signal and right brake light. Thats the light I cannot get access to the plug.

The right turn signal flashes fast, the front light works, the rear doesn't, the right running lights work, but no brake light.

If I remove the wheel and liner, will I be able to get access to the taillight plug?

There is a chance the light socket is bad and replacing the light may fix the problem. That beats pulling the harness or replacing the multiswitch.

 

[bmcgc]

I removed the mudflap and one push pin from the liner and was able to gain access to the taillight connector. I ran out of daylight and had a couple nice helping of dirt. Tomorrow I will get the old light out and plug the new one in.

There is very little slack in the harness, no way that is coming out of the tub through the taillight hole.

Fingers crossed that the lights work, otherwise I have either a harness problem or a bad multiswitch.