hey all - i need help trying to figure out a strange problem i am having with the trailer wiring hookup next to the hitch on my '98 4runner. basically, i have only been able to get current on the wire that controls the running lights of the trailer. i took a tail-light bulb and was testing the different wires in the connector. the running lights work, but brakes and turn signals do not. i can't find any fuses related to this connection, so i don't really know what to try next. any help is greatly appreciated. thanks,

wally

 

Mine is the same way. None would work when I bought my truck, so I used my dremel tool to clean the round connections inside the hook-up part. My running lights work now, but the others still do not. I have not investigated further since I never really pull my trailer. I would like it to be fixed when I do use it though. I guess I need to check to see if I am getting current to those connectors.

Maybe that is your problem. Just a guess.

 

Ohm the wires that are not working to ground and also to each other. They should read 0. I have a 98 also I will try to get some readings on mine in the morning. Good luck

 

I had a similar problem after many years of not using my trailer harness and then trying to use it for the first time since I bought the runner. What I found was that there was a loose pin that poped out of the factory Molex connector inside the runner behind a panel of the right hand side of the rear of the cargo area. Follow the harness up into the runner and you will find it, but its a pain to follow it up the rear by the spare just remove the plastic trim that runs aross the rear of the runner and the carpeted area and that will help from the inside.
good luck on your search...

 

This thread may help

There is a black converter box located inside the left rear cargo panel which takes independent stop/turn and combines them for trailer stop/turn. Place a voltmeter or bulb on the inputs and see if things work. This box costs $200 from Toyota, and it doesn't protect itself very well from trailer wiring shorts. Go to Pep Boys or Autozone and get a replacement converter for $30 or $40.

 

I have the same problem on my 99 4Runner with the Toyota 4-prong trailer hook-up. Does anyone know if the converter box is behind the left or the right rear cargo panel on a 99 Runner? Or somewhere else? I've looked in the obvious places, like inside the taillights.

 

Mines a 96 and behind the right rear panel so not sure if a 99 the same

 

The converter box on the 99's are located behind the left panel, get this replacement box, it's a direct bolt in unit, no splicing of wires:

http://www.kwikhitch.com/miva/mercha...gory_Code=wire

 

Thanks for the tip

 

update: well, luckily i got a digital multimeter from my dad for my birthday. i tested for current at the harness on the bumper, and had the same signal i figured out earlier (taillights, no brake / turn signals). tore out the plastic trim on the driver's side rear of the car, and found the toyota converter box. i had signal going into the box, but not coming out of it. i ordered a new convertor (not toyota, as it looks like from all the research i did that they commonly go out) from here: <http://www.kwikhitch.com/miva/mercha...uct_Code=63415>. it should be here on saturday; if i don't make another post in this thread, assume that it fixed the problem. thanks for all the help,

wally

p.s. this is the company that makes the convertor box: <http://www.trailerwiring.com/>.

 

The only difference with the new kit is the box needs to be routed on the passenger side, but since you need to loosen that side to get to the connector plug, it's no problem to install it. But if your intent on mounting it on the drivers side, simply switch the turn signal wires at the connector.

 

yes I see this is a 5 year old post but the problems remain the same

thank you oh search button

 

I just had this issue on my 98 4Runner. I ordered the Hopkins kit part number 43415 from Amazon. At the time of this post, it was $30. It's the plug and play kit. One gotcha I experienced is that while my factory converter was on the inside of the drivers side panel, the Hopkins needs to be placed and connected on the passenger side. I discovered that when the blinkers were opposite to the truck after it was all connected.

I had the same issue as the OP, running lights worked but no brake or turn signals. Happy motoring!

 

I had rewire my whole socket on the back of my runner, I had to trace back wires, the guy that had it before me, had cut wires out from the loom and tapped them back into the rear tail lights, it was a nightmare. But nothing a multi-metre couldnt fixed. Ended up tracing back all the wires and set up the socket so it would suit any trailer that i pulled into it.

 

anyone have the oem Toyota part number for the converter box?

Thanks!

 

Yes, I need the part number also!