Rear door wiring

This should be posted with the thread linked below (but it has been closed).

https://www.turbodieselregister.com/threads/no-dome-light-when-opening-lr-door.264059/#post-2548704

I repaired the wiring harness between the B pillar and driver side rear door. The typical problem existed where the dome light did not come on after opening the door. Many of us have noticed that the sharp bends in the wire tend to eventually break wires.

Sure enough, one of the wires was broken. At least half of the wires looked like they would be broken soon. I was impatient and wanting to do the job on the cheap so I used some regular automotive wire that I had laying around (rather than ordering wire that is more appropriate). Here is an idea for an improvement which might make the harness last longer.

McMaster Carr has wire that is supposed to be more tolerant of flexing. One downside to this is the outside diameter of the wire is a good bit larger (a little more than double the OD of OEM wire). Not sure if the thicker wire would squeeze through the opening in the door 'grommet'. Search their site for ultra flexible wire. Abrasion-resistant wire is one choice that may work. This document shows the colors and gauge sizes of the wire. The link for abrasion-resistant wire is to 14 gauge wire. You'd have to buy 10-foot lengths.

I found that Geno's has the Mopar wiring harness. That's surely less hassle than cutting and soldering / crimping. Feel free to correct me, but I don't think Mopar has used a more durable wire in the replacement harness. My OEM harness probably lasted ~ 120K miles before wires started breaking so maybe we could expect the same from a replacement harness.

 

Yeah, Thanks I need to repair mine, my pass. side rear door is same, I open door and dome light doesn't work , is it pretty easy fix?

 

I just threw in the Mopar part from Geno's a few months ago on my 06. The job couldn't have taken an hour. I don't have anything to add about wire quality but the first one lasted 14 years, I doubt I'll have this truck in another 14.

 

Same problem on my 2003. Had three wires break, so i soldered & heat shrinked lasted about a year with a failure with one wire.

 

Hi. So is there a dealer part#, a replacement harness for these trucks? I’m looking into buying one of the 3 Gen. trucks. It seems it’s a common issue on the rear doors. If there was a replacement, a better harness part available, that would be a great options for many owners. I’m trying to learn as much as I can about the 3 Gen.

 

Mopar part # is 56051931AB

That said, Dorman makes an aftermarket rear door wire harness that is supposed to be made from slightly better quality wire though some people claim that the rubber boot is not as good.

The Dorman Part # is 645-506 for either rear door wire harness on a 3rd gen quad cab. Amazon has it for $95 with prime shipping.

 

Thank you guys!

 

When I replaced mine I asked someone at Geno's about the Dorman replacement, they said they quit carrying it due to too many problems. I didn't ask for specifics so take that for what it's worth. Went with Mopar.

 

One thing worth trying is to electrical tape all the wires together so they support each other and no one wire can bend really sharply. Both rear doors on my truck had wires break and, in order to buy time to decide whether to replace the entire harness or to patch in larger, more flexible wire to replace the original wires, I did a temporary patch job with crimp connectors. Many years later I had to repair the drivers read door again (same temp patch job). The passengers side rear door is still working. As part of the temporary fix I taped the wire bundle together so the wires with the butt connectors wouldn't just break again from flexing right where they went into the crimp connectors. I attribute the longevity of the temporary repairs to taping the wire bundle together. If I were to buy a new harness or splice in new wires correctly, I would definitely tape the wires together in a bundle as a sort of strain relief measure.

 

I suggest using RC wiring instead of automotive wiring. RC wiring is much better quality than automotive wiring. It costs more, but do you really want to do the job again?

 

Dorman rubber boot is proven crap, but the wires are fine.
Reuse the OEM boot and all is fine.
BTDT