i dont know if your model of 4runner has this or not, but on my 1990 4runner 4DR 4WD 3.0L V6, there are 4 wires coming from a white box under the rear bumper on the drivers side. coming from the box is also a few wires that go to the right side brake light asembly. the set of 4 wires that do not connect to the brake lights, is your trailer brake wires that conect to a simple 4 way triler harnes, and you can even plug it into a 6 or 7 way harnes if you want to go overboard. The little white box that is on my truck could very well be an aftermarket part, so i would suggest going to your local Truck shop and have them take a look if you cant figure it out.
"Where can you download free wiring diagrams for a 92 Toyota 4runner?"
In the book.
go to a reputable auto parts or trailer supply store and purchase a trailer wiring loom that is specific for your vehicle. it is a unplug existing, plug in new ("t") loom affair. included in this loom is a "converter" for Toyota specific light systems. standard trailer system (2 bulb) Toyota (3 bulb). probably 30 to 40 unless you purchase at dealer. my Toyota was an '89 but I'm confident that this is the route to take.
where is the neutral safety on my 1987 4runner
It should be by or under the rear of the vehicle.
could be the wiring to the dome light
Many vehicles do not come equipped from the factor with trailer wiring. You may need to connect them yourself or have someone do it for you.
T-Connectors are an easy, convenient way to connect your trailer wiring to your tow vehicle wiring. T-Connectors are specific to your vehicle's wiring. Simply unplug existing vehicle wiring harness and plug in the T-Connector.
Fuse is located on the positive battery terminal labelled F/L 30A
i just found my 95 4runner SR5 light reminder relay in front of my shift levers and behind the panel below my radio. i went to Toyota parts department and request to look at the EWD (electrical wiring diagram) to get a general location for my vehicle. PHIL
1988 Toyota 4Runner Troubleshooting (check in this order): 1. Check Fuses 2. Check Bulbs 3. Check Light Switch(es) 4. Check license plate light bulb and wiring 5. Check trailer hitch wiring harness 6. Check all wiring harnesses and wire Most likely its the fuse or a burnt bulb breaking the circuit. See sources and related links below for bulb information. Sometimes the license plate and/or the trailer hitch is wired into other circuits and can cause issues in other areas. Sometimes its wires grounding out somewhere on the vehicle. See sources and related links below for bulb information. See owner's manual for location and identification of fuses.
Go to a U-Haul dealer they have the wiring jig you'll need.