1990 12v HZJ75 - Exploring a Hacked Up Wiring Harness

[TreadingLight]

Any idea what these two connectors are for? I found them dangling/disconnected under the dash by the left-hand kick panel. One is 3 pin and the other looks like 8.

 

[roscoFJ73]

Is there much not working? The one with 8 wires looks like its from where all the interior wiring comes through a hole in the firewall.

 

[TreadingLight]

All interior lights and dash functions work (at least they did before I started looking around). My first thought is these are for some optional accessories/features but I guess I should make sure I didn't accidentally disconnect something when I pulled the kick panel off (seems unlikely).

 

[roscoFJ73]

Is the heater fan installed and working?

 

[TreadingLight]

Yes it is - blower blows and all the other accessories seem to work too.

 

[TreadingLight]

Resurrecting my thread. I must admit that after a marathon sprint of fixing bad connectors and splices, I slapped it all back together more or less the way I'd started. Stout but messy. Everything was charging and my attention went elsewhere. A nagging thought here or or there would sometimes remind me I had a troubleshooting nightmare waiting the next time something went wrong, but mostly it just ran without complaint.

Until one day in a remote arroyo in Baja. The starter wouldn't engage. Click. Click. After some fiddling I found the aux battery had failed. Aux battery. Starter motor. That should be on the main battery. Ug. I got going with some creative (semi-random) recabling but resolved to dive back in to fix it properly before any long trips.

So here I am. I have identified most of the cables and have ordered parts to get this sorted. There are a few leads however that I'm still not sure about. For context, I'm setting this up with a solid state battery isolator and two 12v batteries. Charge and aux battery goes on one side. Isolator acts like a diode allowing current to flow through to the main side but not vice versa. All stock Toyota electrical loads should should end up on the main battery. Aftermarket loads like the fridge and the offroad lights will go on the aux battery.

Unidentified Leads:

1. White cable, blue diamond marks, ~8 gauge, coming from the LH (passenger) firewall and connected to the positive battery terminal. Main charge to battery?
2. White cable, blue diamond marks, ~10 gauge, coming from the LH (passenger) firewall and connected to the positive battery terminal.
3. Red cable, ~12 gauge, coming from the LH (passenger) firewall and connected to the positive battery terminal.
4. Dual conductor cable on the alternator.
   1. White cable, blue diamond marks, ~8 gauge. Has continuity to #1 above so I believe this is the main charging cable to the battery. I'm moving this to the aux side of my system.
   2. White cable, blue diamond marks, ~10 gauge. Not sure what this is. If it's providing power for any of the vehicle's main circuits, I'd want to put it on the main battery. If it's to do with charging (drives the gauges maybe?) I'd put it on the aux side. Does not have continuity to #1 or #2 above.

Plan to make a fusible link cable / adapter with metripacs to get all this organized and want to be sure I'm putting everything on the right side of the isolator

In particular that dual-conductor alternator cable. Any suggestions?