RTH 80 Series wiring harness (complete) (1 Viewer)

[concretejungle]

I'm in the process of replacing my entire wiring harness from the computer out to the block plugs/sensors.

I did a search and didn't find a lot of information on this swap, or perhaps i missed it.

Flipping through my FSM i haven't been able to locate a complete diagram of the wiring harness. Reason i'm asking is without removing the intake (which i'm starting to think is necessary) it appears that the wiring harness runs back and over the top of the transmission. Can anyone confirm this?

 

[chap79]

Yes it does.

 

[chap79]

 

[NLXTACY]

Yes to the intake.

 

[concretejungle]

thanks! It seems like the only way i can get to the two large plugs that are just beside what's labeled P1 in the diagram above is to remove the intake.

 

[Tedward]

I've read where people have cut the 'webbing' of the plenum. Meaning sawzall a piece out of the upper and lower plenum at the mating surface. Hard to describe without a pic. Presumably to aid with the remove-install of the main engine wire harness. Also, it may allow one to keep the harness further from the EGR tube. Pretty sure Beno did this to his old 80 wagon.
Not sure if that helps, just throwing it out there.

 

[concretejungle]

Stopped messing with it for the day. I got almost everything unplugged. Now i just need to get the last bolt of the intake off so i can remove it. I think that will make a big difference.

 

[concretejungle]

OK, got the old harness out yesterday. From what i experienced, i did NOT need to take the intake off. I did need to remove the front DS wheel, and the starter. This allowed me to get to the large two plugs that are located just behind the starter. Also, i removed the EGR valve. These three items allowed good access.

Here is the old out and now i'm prepping the new one for install. I want to wrap it with extra heat wrap and i also have to extend the IAC and TPS sensor plugs because of the supercharger, and, i almost forgot that i had a rear O2 simulator that i had gotten from lilevo a while back. So i need to splice it in as well. Also, i found out that the plug on my front knock sensor had broken off completely. All that was left was a little piece of metal. So i'll order a new one of those guys today.

I will probably do that today and start putting it all back in tomorrow. It's amazing how these projects grow. It always seems to be a situation where you say "while i'm in there"....

 

[concretejungle]

Finished up today.

I would say removing the EGR valve, remove the DS front wheel and the starter are necessary.

Extended the TPS plug and IAC plugs, wrapped the wiring harness with heat tape and wired in the rear o2 sensor modulator. Got everything done today.

 

[landtank]

I remove the upper half of the intake as well as the wheel and starter. I also lower the transmission at the rearvwhich helps with the wires ghat go over it .

 

[jaymar]

View attachment 1459618

How many wiring harnesses are we looking at here? This appears to be two, maybe three...?
The one on the engine being 82121-60343.

 

[chap79]

How many wiring harnesses are we looking at here? This appears to be two, maybe three...?
The one on the engine being 82121-60343.

8. The harness in question in this thread is the Engine Wire

 

[SmokingRocks]

where did you source a new harness from? and how much?

 

[concretejungle]

that was an older thread from 2017 but I purchased the wiring harness from Beno at that time.

 

[ajax1]

I bought mine from local Toyota dealer he gives me a discount, bought it in 2020 I think it was around 400 bucks