Wiring Rear Lights (1 Viewer)

[burnt03]

I'm putting in some taillights in the back (inset ones w/ the rubber grommet around them) and using a trailer adapter in order to use the one pair of lights for tail, stop and turn lights.

I was just wondering whereabouts (on a 1978 FJ40) the harness comes down from the steering column and splits down to go to either side? Save myself some rust and dirt in the face trying to dig thru everything

Thanks

 

[Eternal]

Just wondering why don't you just use the wires that go to the tail lights. Cut em remove the old ones and put on the new ones. Are you having 2 sets of lights? Don't quite get the trailer adapter. What's that for?

 

[burnt03]

I tried that w/ an old set and it didn't seem to work. From previous posts on here, it seems the best way to go about using a single pair of lights is either w/ the trailer adapter or w/ diodes (which I wouldn't have a clue how to go about using).

Only have room on the bumper for one set of lights (see the pic) and if I try to wire up the signal lights along w/ the stop lights, every time I try to signal, they both flash, like hazard lights usually would.

I'm probably not very clear here, but hopefully someone can save me some digging around

Oh yeah, I forgot. I could just use the wires going to the taillights, but just trying to keep it half assed clean (so I don't have to bring both sides together in the centre to the adapter and then split them back out to the lights to either side again).

 

[Poser]

There is a junction on the passenger side firewall, where the rear harness of the truck connects to the main electrical harness. You can either wire in your converter there as woody did, or mount it in the rear of the vehicle. I have done the latter, splicing into the Toyota rear harness on the passenger side rear of the frame where the harness splits to go to the left and right sides of the truck.

Pretty strait forward install, just make sure that you seal any connections, or preferably soldier, and that you have a good ground in the circuit. Both of these items create all sorts of electrical irregularities that have people pulling their hair out regularly.


Good luck!

-Steve

 

[burnt03]

Well, I found where it splits (thanks for the help) and have all the wires labelled accordingly (even found a reverse wire that works! Wow!)

Anyways, having new troubles. Wired in the trailer harness and it doesn't seem to be working as planned. Have it as follows...

Yellow Wire - left: stop and turn lights
Green Wire - right: stop and turn lights
Brown Wire - running lights, license etc
White Wire - ground (both sides of harness to one ground...?)

But even before I wired the ground, I hit the brake pedal and the signal lights both came on (front as well).

What am I missing here?

 

[Poser]

So you are saying that now that you have a known, good ground, that when the brake pedal is depressed, that the turn signal lamps up front light up? Not having a good ground will create this scenario. I would verify this for starters.

Also,

In a single bulb, dual fillement system, the turn signal and brake light share the same fillement, and the running light is the dimmer of the two. So, if you are expecting to have brake lights and a turn signal on the same side in the rear, you will not get that at the same time. The brake light will be on, on the opposite side that you are using the turn signal, and the turn signal will be flashing the same brighness as the brake light.

I would use the frame, and clean a spot to bare metal. You do not need to 'share' a ground point if you do not want to, but you can, it is not required, so long as all ground points are good, and not rusty.

Good luck!

-Steve

 

[burnt03]

Ok, I prepared a new ground as you suggested and I seem to be having the same problem. I have a feeling that I'm committing some stupid wiring mistake that my rookiness is not picking up.

I realize that I won't have a brake light and turn signal at the same time as well. I've followed lots of these vehicles wishing that one day, mine might do the same

I'll see if I can include a picture of how I wired it and maybe you'll see something I'm oblivious to. Thanks for all the help by the way.

 

[hammerhead]

Your brake wire is with the turn wires and feeding back. I think I have a converter in stock at my shop. I'll check the instructions tomorrow.

 

[burnt03]

Yeah, it says on teh back of the package for the trailer converter that I'm supposed to wire the Right turn/stop wire to the green wire and the left turn/stop light to the yellow wire. How can I prevent the voltage coming back into the signal circuit?

 

[Poser]

Is the electricty flowing through the piece the proper way? There is a vehicle side and a trailer side. Your rear lamps need to be hooked up to the trailer side, and the vehicle harness attached to the vehicle side...

There are diodes inside the converter that do not allow the current to flow back through the system, but it has to be wired properly in order for it to work...


Just a thought...


Good luck!

-Steve