Well, finally got the "correct" backup and 4wd harness, but, it didn't have a plug on the end of it where it goes to the under dash harness. I'm guessing that sometime Toyota decided to change the 3 wires from this harness from going directly into the harness to having a plug coming out of the harness to plug into. The plug makes more sense. The good news is that they kept the wire colors the same, R, R-Y, and R-B, all the wires from the harness to the dash harness plug match! YEA


So, another wiring problem solved......................I think...................won't know till I energize everything way down the road, but it's off my "to do list"
Next, new ground wires, I think 3 or 4 total, wires to the terminal blocks, both switched and unswitched, battery positive and negative cables and the alternator charge wire. AKA the big 3........modifications
Anybody do this upgrade? If so, what gauge wires did you use? I'm leaning towards 4 gauge for all the ground wires and 0/1 gauge for the battery cables, and only AWG wires. They all will be custom lengths so I can put them where they look the best in the engine bay.

 

Update
I added a plug to the harness where it plugs into the under the dash harness, the harness I got didn't have a plug on the end, (it was attached directly to the under dash harness) also changed that plug to mate with new plug.
I plugged the tail light harness into the under dash harness where it feeds the tail lights, I attached a 9 volt battery, added my tail lights to the harness and the backup lights went on. So, I believe that the backup light circuit is done.
Then I attached the plug for my gauge cluster, put power to the plug that goes to the 4WD switch and the light on the dash went on. So, I believe that that circuit works also,
Haven't check the actually backup light and 4WD switches yet, but if the 2 switches work I should be good.
Next is the charge lamp relay and the charge light on the gauge cluster. That one gets a little more complicated
Getting there

 

While playing with the under dash wiring harness I think...I found the 4 wires that feed the clock. Unfortunately the PO cut the plug off! I guess I'll be looking for that plug.
We having fun yet?

 

Hi Mike,
Backup light should only come on when backup switch is turned on.
Sorry, hard to follow. A diagram where you connected stuff would be easier to follow. Please send bigger resolution of your backup light schematic. One above is too tiny to work with.


Cool.
Is this how you did it?

TEST FOR 4WD INDICATOR:
I'll work on that, Preparing for weekend trip today.

 

Hey Ray
Where are you going this time?
All I did to test the backup lights was I applied power to the plug that attaches to the switch, connected the harness and the tail lights just to make sure that I had connection. I think that is a done deal. I did the same for the 4WD and the dash lite up so I think that is done as well.
Here's a bigger pic of the backup schematic:


But like I said, I think that these two circuits are good
Have fun where ever your going!

 

So Cal Mountain to commiserate with friends back east - LOL
Camping here and climbing to summit.