I just learned all about my 4 pin wiring, and am here to share.

Your 4 pin may not function correctly either. Depending on your year of 4Runner you may have a taillight converter "black box" in either your driver or passenger side rear cargo compartment.

Verify where it will be before you remove all your interior trim panels.

For my 99 the black box was in the drivers side rear corner.

A 6 pin connector feeds signal to the box at one end and a 4 pin output connector feeds that "converted" signal to your 4 pin connector near your hitch.

My suggestion is buy a "HOPKINS #48055" this is a replacement 4 pin connector with built in LED lights to indicate the working functions.

The wiring colors will match up pretty easily with your existing wiring. You can bypass the converter box completely ( I did) and wire up the Hopkins wiring direct to the 6 pin wiring.

If you look closely at your 6 pin connector-you will notice it only contains 4 wires anyways. Be sure to properly record which wire is which . Taillights and brake light functions are combined into one of the 4 wires-one is a ground, and that leaves two wires for the turn signals.

According to my research the converter box shorts out when it is connected improperly. Best bet is to eliminate it.

EDIT 05302009: HA- You simply can't eliminate the tailight converter box. It is a necessary device to convert 5 input functions to 4 output wires of the 4 pin connector. However if it is defective it can be replaced with Hopkins #43415 which is a plug and play application for Yotas.

Be sure to test all 4 LEDs of the Hopkins device and the rear stop and taillight functions before you put your back end all back together again.

I was able to figure this out. If you need help with it I can help you talk it through.

turns out I wired my brake lights to the parking lights.

When I step on my brakes now I light up my parking lights as well.

Turns out the purpose of the taillight converter box is to allow electric current flow out of the 4Runner to the 4 pin connnector and not backwards up to the 6 pin connector.

I'll update again when I am sure I am fixed. The 4 pin is working great ....

I have edited the original posting to reflect the true "fix".

If you need help understanding your 4 pin connector and why it is not working properly I can now help you out.

I highly recommend the Hopkins kit #43415 ($34.75 Amazon-free shipping). If your truck or 4unner never had a 4 pin connector out back then this kit makes it a plug and play experience. It includes the 4 pin connector and enough wiring to route it out your back end to the hitch area.

If you already have a taillight converter box and it went bad-this unit can be spliced into place.

The 5 functions in are:


1/ Headlights-Parking Lights
2/ Brake -stop lights
3/ Right Turn signal
4/Left Turn signal
5/ Ground

This kit in combination with Hopkins #48055 ($7-Autozone)makes it easy to monitor your 4 pin functions from outside your vehicle with the LED indicators.

I was about to hook up my buddies trailer yesterday when I ran into this problem. My trailer lights used to work, but now they don't. I found the black box and removed it. Now I need to get these kits and install 'em. Thanks for the info, Ron!

If I run into any problems, I'll hit you up.

Yeah! The new kit did the trick. Thanks Ron!

sweeeeet

Ron (or anyone) - I opened the panel in the DS rear area, but found NOTHING there in the way of a wiring harness or converter box. Tried to look into the passenger side, but the cargo box really obstructed my view, and the only thing I found was the aux +12V outlet.

Is there somewhere else that Toyota might have hidden my wiring harness? I have the rear hitch, just no wiring.



To be clear, this is on a 99 Limited...

z cruiser sorry not ignoring you -just could not reply while I was banned by some overzealous moderator -geez who could it be?

Your hitch does not look to me to be factory-I presume you have never had the towing package option-and perhaps that hitch was added by a previous owner.

You need to do the entire plug and play kit from Hopkins-you will have to access both corners of the rear end and go from there to snake the wiring out the back end to the hitch area.

Which you probably figured out months ago....

Lol, never had to install it...

Ron,
Good info! Thanks. I modified the title just a bit for future "searchers".

zcruiser,
That sucks! Hope everybody is ok.

[QUOTE=Ron Helmuth;411940]I just learned all about my 4 pin wiring, and am here to share.

Your 4 pin may not function correctly either. Depending on your year of 4Runner you may have a taillight converter "black box" in either your driver or passenger side rear cargo compartment.

Verify where it will be before you remove all your interior trim panels.

For my 99 the black box was in the drivers side rear corner.

A 6 pin connector feeds signal to the box at one end and a 4 pin output connector feeds that "converted" signal to your 4 pin connector near your hitch.

My suggestion is buy a "HOPKINS #48055" this is a replacement 4 pin connector with built in LED lights to indicate the working functions.

The wiring colors will match up pretty easily with your existing wiring. You can bypass the converter box completely ( I did) and wire up the Hopkins wiring direct to the 6 pin wiring.

If you look closely at your 6 pin connector-you will notice it only contains 4 wires anyways. Be sure to properly record which wire is which . Taillights and brake light functions are combined into one of the 4 wires-one is a ground, and that leaves two wires for the turn signals.

According to my research the converter box shorts out when it is connected improperly. Best bet is to eliminate it.

EDIT 05302009: HA- You simply can't eliminate the tailight converter box. It is a necessary device to convert 5 input functions to 4 output wires of the 4 pin connector. However if it is defective it can be replaced with Hopkins #43415 which is a plug and play application for Yotas.

Be sure to test all 4 LEDs of the Hopkins device and the rear stop and taillight functions before you put your back end all back together again.

I was able to figure this out. If you need help with it I can help you talk it through. [/Q

Hey Ron i have a 99 4runner the 4way conector doesent have power i took of the converter and checked the connection comming in 2 the converter for power but it was dead do they have a fuse or something

It's quite possible a fuse is blown-but typically that would have affected other circuitry like the tail or stop lights or both.

There wouldn't be just two wires coming into the converter. So it's my guess you are checking the wrong 2 wires.

Have someone to assist in the drivers seat and turn on parking lights, hit the brake pedal and so on to determine the correct sequence or color coding of the wires.

One wire from the box feeds a ground wire of course.

Let's see a picture of what you are seeing for more help.

Hi,

So I just bought my runner and it has a hitch on it. I got underneath yesterday and found the wires to hook up already run to the hitch. It just does not have the 4 pin connector on it yet. I have one and all the wires match and I thought I could just splice it in and go. Am I wrong? I have not had time to actually do it as I am working some long hours. Any help is appreciated.


P.S if it matters it is a 99 SR5

In theory zonianbrat yes you could just splice in your 4 pin and be ready to go.

But the fact the 4 pin is cut off or missing makes me think you will have to wire up your new 4 pin wiring back to the tail light converter box area. For a 99 that will be in the drivers side rear cargo area back corner.

Well that just sucks.

I got some days off soon. I will wire it up and hook up to the trailer and drive it around for a day and see what happens. Thanks for the reply!