Toasted Lower Dash and Passenger Side Body Wiring Harness Connectors (1 Viewer)

[Fzj80 1997]

I bought a built out low mileage 2014 for a smoking deal the other day knowing full well that it had a sunroof leak for a decent amount of time. What I did not know was that the 200 is not an 80 series in that a sunroof leak will absolutely **** s*** up.

Last night before bed, I was ignorantly looking into the best way to clean out the drains (they’re still clogged). I kept seeing threads and posts about how people were getting absolutely destroyed from water getting into the floor boards and seriously damaging the wiring harness on these trucks. I ended up not sleeping very much last night lol. First thing this morning, I ripped out the trim pieces to find absolute carnage on the lower connector. The other ones aren’t so bad, but the one closest to the floor board on the passenger side is completely roached. The driver side is perfectly OK which could be attributed to the kdss lean the truck is currently having resulting in the passenger side being lower.

My question for you all is, what should I do?

A. Replace the entire dash harness and passenger side body harness ~$4k in parts and a ridiculous amount of time and effort

B. Try to source the factory male and female pins and connectors and try to rebuild the harness in the affected areas. Not really a fan as the way this is set up is clearly an engineering flaw. The connectors should have been sealed.

C. Rebuild the harness in the affected area with Deutsch pins and connectors. Nice, well engineered pieces that are weatherproof.

I would really appreciate it if those that have dealt with the issue by going the non traditional route (no whole harness replacement) could help guide me through what you did or provide links that you followed to get it working right and reliably. A source for an electrical diagram would also be extremely helpful.

The carnage:

 

[Fzj80 1997]

Part numbers and pricing for the OEM harnesses and carpet for those interested

 

[Fzj80 1997]

Also, the symptoms this truck currently has is the passenger seat controls don’t work, the airbag light is on (weight sensor probably goes to the roached connector), and the front passenger door sensor doesn’t sense that the door is open.

 

[nwfl4runner]

If not your daily, I’d just label and disassemble and clean the connectors - no reason to replace that harness

 

[Fzj80 1997]

If not your daily, I’d just label and disassemble and clean the connectors - no reason to replace that harness

I had my fingers crossed hoping this was all I needed to do as I unscrewed that 10mm bolt holding the connectors together. Unfortunately, some male pins came right out with the female terminals, so this isn’t an option for me

 

[Malleus]

I had this same thing happen to me a couple of years ago. In my case, an insurance claims paid for everything, but I was in a rental for 5 months (no lie), waiting for Toyota to receive a new dash harness form the vendor. I would never have paid for it, and the engine harness, which State Farm replaced.

Way easier to spend a weekend depinning the connector housings and spraying them with CRC plastic safe cleaner and polishing the terminal ends with Deoxit. You can get new Sumitomo terminals from Ballenger Motorsports. Pick up a copy of the wiring harness repair manual; it's very handy. I don't know how I lived without it.

Agreed this is a serious design flaw, but Toyota has never used sealed connector housings inside the cabin. Just as with the 80s, they assumed the sunroof wouldn't leak.

 

[doru]

Harness replacement is a major PITA. Just repair/replace the connectors. In the worst case you can bypass the connector for those destroyed pins using wire, but I would still use some kind of connecter on that wire. Still not fun but a LOT cheaper and faster.
But before doing that, get that sunroof fixed!

 

[bloc]

One note for people coming along later: the above part numbers should be considered valid for that specific vehicle only.

There were so many part number changes with these things that the FSM and parts diagrams explicitly state techs should get the part number off the harness installed in the vehicle before ordering another, rather than consulting diagrams.

Good luck with things. It’ll take a while but motivated person can handle it.

 

[Fzj80 1997]

One note for people coming along later: the above part numbers should be considered valid for that specific vehicle only.

There were so many part number changes with these things that the FSM and parts diagrams explicitly state techs should get the part number off the harness installed in the vehicle before ordering another, rather than consulting diagrams.

Good luck with things. It’ll take a while but motivated person can handle it.

According to the parts guy who is very competent, it is the body harness that runs down the sides that is option dependent and even giving the VIN does not tell you which harness you have. You need to pull the old number that is printed on the harness itself.

The instrument cluster/dash harness should be the same

 

[Fzj80 1997]

Does anybody have some input on the best way to de pin the connectors and if there is a specific tool that used? Some of the pins are very small

 

[TeCKis300]

I'm with @doru . Just bypass the connector for any failed pins and jumper with straight wire. I wouldn't bother adding any new connectors. It'll be a more reliable fix and it's already going to be a PITA with access, having enough wire length, and packaging. Having a connector there is more for vehicle assembly anyways and unless you intend to do a full harness replacement, there's no point.

 

[bloc]

I'm with @doru . Just bypass the connector for any failed pins and jumper with straight wire. I wouldn't bother adding any new connectors. It'll be a more reliable fix and it's already going to be a PITA with access, having enough wire length, and packaging. Having a connector there is more for vehicle assembly anyways and unless you intend to do a full harness replacement, there's no point.

I’d agree with this, and add that properly done open barrel crimps are the best method when longevity and vibration resistance matters. Even better than soldering due to strain relief. Then add heat shrink for short resistance.

This will be a challenge with how small many of the wires are, but also won’t take up as much room as the standard barrel crimps once all those wires are crimped in the same spot.

I can dig up a great document on race car harness building if you want some pointers on what to look for. The parts and tools they use are over the top in this application but the concepts would apply nicely.

 

[doru]

@bloc, if you manage to find the doc I'm interested to. Thx!

 

[Willie G]

@bloc, if you manage to find the doc I'm interested to. Thx!

+1 and Thank You in advance!

 

[Leaky2014]

Hey admins, please make a sticky thread addressing this issue with our trucks, it could really save some people a lot of headaches.
It seems to be a matter of when not if. One a month at least pops up on here.

 

[bloc]

@doru @Willie G

Enjoy

Motorsports ECU Wiring Harness Construction

 

[Willie G]

@doru @Willie G

Enjoy

Motorsports ECU Wiring Harness Construction

Thank You!

 

[FrazzledHunter]

@doru @Willie G

Enjoy

Motorsports ECU Wiring Harness Construction

I looked at the document and was taken by the "Aerospace Wiring" photo. In my career I had the privilege of seeing spacecraft being built at Johns Hopkins Applied Physics Lab and other spacecraft manufacturers. Not only does the wiring on a spacecraft have to survive the horrors of launch and space it has to be wired and assembled in a way that is spin balanced in 1 or more planes.

 

[KLF]

I looked at the document and was taken by the "Aerospace Wiring" photo. In my career I had the privilege of seeing spacecraft being built at Johns Hopkins Applied Physics Lab and other spacecraft manufacturers. Not only does the wiring on a spacecraft have to survive the horrors of launch and space it has to be wired and assembled in a way that is spin balanced in 1 or more planes.

I'll add that I grew up in MD (Parkville/Towson) and had several school field trips to the APL, that place made some cool stuff.

 

[bloc]

Not only does the wiring on a spacecraft have to survive the horrors of launch and space it has to be wired and assembled in a way that is spin balanced in 1 or more planes.

Yeah, hopefully no 200-series ever finds that truly necessary, but the concepts and methods are really interesting to nerds like me.

More relevant to OP, I have started using the open-barrel crimps for my wiring work and while more time consuming I definitely prefer them. This thread shows some of what I did to repair a squirrel chewing on my harness a while back, “after” pictures in post 18. Note that a guru (taco2cruiser) provides input on the type of wire to use when possible.

Chewed harness repair resources

@Taco2Cruiser and other gurus.. what kind of wiring does toyota use? Particular ratings for under hood vs interior environments? A squirrel decided to make a nest of my engine bay and I want to do as good a job with the repair as possible. I've figured out how to find connector part numbers in...

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