FJ40 Wiring Harness (1 Viewer)

[Kanda]

After many idle years, I am attempting to complete the rebuild of a 1981 FJ40. Unfortunately, I did not document the wiring disassembly very well. Can anyone point me to any useful resources or offer any guidance that will turn this seemly overwhelming task into a simple one .

Also, I have installed the tub onto the chassis - should I install the fenders before attempting to install the harness? It seems like several wires attach to the fenders. Thanks!!

 

[Malleus]

FJ40 wiring

 

[martymart]

I use Mark Baker from the link that Malleus provided you. He built my entire wire harness and I purchase my electrical connectors from Mark.

 

[pjohnson]

I don't think he's building harnesses anymore, but he sells the wire, connectors and tools.
@Coolerman

 

[Kanda]

Thanks - any thoughts on installing the wiring harness while the fenders are detached? Or does it make sense to install them and then install the harness?

 

[pb4ugo]

I would install the fenders once i was sure all my mechanicals are done up frt. I 1st ran the harness under the dash, out the fire wall then under the tub to the rear. The frt portion was fed thru the firewall and just dangled there. The frt harness is pretty easy to run and was one of the last things I did.

 

[peesalot]

x2 on letting the front stuff hang out by the brake booster, FWIW a test light, some aligator clipped jumpers ( 2 ft), and a small 12v batt( like the big square ones from when we were kids) come in handy. Even when you get a harness you will find that being able to identify & test will be necessary IMO.

 

[Pitter Patter]

An 81 will have a front harness coming out both driver and passenger sides of the firewall. Agreed on letting it dangle, at an angle, until you are ready to hook up everything in the engine. Hit me up if you have any questions. Mine is labeled.

 

[Fast Eddy]

Agreed on letting it dangle, at an angle, until you are ready to hook up everything in the engine. Hit me up if you have any questions. Mine is labeled.

At what angle should it dangle?

 

[Pitter Patter]

The one that prevents any mangle

 

[Fast Eddy]

Does the angle of the dangle that prevents mangle also help with tangle?

We'd better stop before a mod decides to strangle.

 

[Kanda]

Thanks all - this is most helpful - even the commentary of the angle of the dangle.

 

[Kanda]

An 81 will have a front harness coming out both driver and passenger sides of the firewall. Agreed on letting it dangle, at an angle, until you are ready to hook up everything in the engine. Hit me up if you have any questions. Mine is labeled.

An 81 will have a front harness coming out both driver and passenger sides of the firewall. Agreed on letting it dangle, at an angle, until you are ready to hook up everything in the engine. Hit me up if you have any questions. Mine is labeled.
View attachment 3143254

What year is this harness from? I did not label mine when I removed it, and regret not doing so now.

 

[Pitter Patter]

1981

 

[Kanda]

Thanks again! Any thoughts on where I can get brackets, hangers, etc. that one would use to hang the wires on the frame/body? I assume the best place to start would the fuse box. Do you have any tips on cleaning the harness itself?

 

[JVZii]

Thanks again! Any thoughts on where I can get brackets, hangers, etc. that one would use to hang the wires on the frame/body? I assume the best place to start would the fuse box. Do you have any tips on cleaning the harness itself?

Sor has many of the plastic wire ties also I think some are available from Toyota.

For cleaning the harness itself. Get a few gallons of evaporust and let the harness soak in it a few days. The wires and connectors come out very clean.

 

[Kanda]

Sor has many of the plastic wire ties also I think some are available from Toyota.

For cleaning the harness itself. Get a few gallons of evaporust and let the harness soak in it a few days. The wires and connectors come out very clean.

Thanks!

 

[phroger]

This stuff is great to wrapping up harness loose ends as well.

I bought some from Crutchfield when installing fog lights and some other wiring:

Scosche EXTAPE​

I saw what looks like an equivalent item on Amazon, FYI (haven't tried the Amazon version, though):

High Temp Wiring Loom Harness Self-Adhesive Felt Cloth Electrical Tape

 

[rghouse]

make sure your main fire wall grommets (2) are installed on the harness with the least amount of wires passing through at once, or when it is in its simplest easiest placement/configuration to work with or else you will be stuck jamming/lubing and possibly tearing the $50 grommet (like me).

The grommets go right by the yellow tape on each harness with bell end facing the (dirty) motor side