Where is the ground wire for the rear tail lights?

 

that is to ground the light,the socket is plastic so it has to have a ground run to it

 

I want to know WHERE it is.

 

I think it screwed to the bed,just working off memory
it's been a while since I had my lights out
I would go look but the truck is 750 miles away

 

I just dont see where the ground wire is for the rear lights. Are the rear lights grounded into the license plate lights?

I also realized the light on the driver side stays on and its the one thats tapped into the trailer light outlet, could that be the problem? Ill try to remove it then see what happens.

Just if I could find the ground!!!!

Maybe Ill make my own ground? the ground on these is black correct?

 

The ground wire runs back through the harness, marries up with the fuel tank sending unit and fuel tank selector valve grounds, runs into the cab, under the dash where it marries up with about seven or eight other grounds, and terminates under the dash just to the right of and slightly above the heater control box. It bolts on from the top, so you have to take the dash pad off to get at it. If you look down from the top you'll see two ground wires bolted to the dash support. It's not easy to see if you have A/C. It's the bigger of the two wires.

 

Yes the ground wire is Black. Circut #57 Black on the ford diagrams.

This circut for the rear lights can ground in two places. Remove the taillamp assymbly and look for a wire grounding itself to the bed of the truck on each side. This is one place it will ground.

The other place it can ground is the charge start run splice that is located under the dash.

What I would do is remove your taillamp assymblies and look for the black wire that is attached to the bed with an eylit connection behind the lamp assymbly. If this is absent, then you will have to trace the wire along the framerail to the front of the truck.

hope this helps.

 

I guess my ground is up in the cab because there is no ground on the bed.

Man this is frustrating me bad, I want to get it on the road but cant cause of the lights

Here is the problem and my trial and error...

Driver side turn signal/run light, really corroded making the light bulb unable to come out.

Rear driver side taillight stays on constantly.

Rear turn signal DOES work.

When headlights on passenger side front and rear turn signal does not work...

I unhooked my trailer light plug but still no change.

My wiring does not appear to be hacked at.

I also grounded the driver side rear turn signal to the bed and still nothing.

My conclusion is my steering column. I went and unhooked the U shaped plug to the turn signals and the problem goes away, the rear taillight goes out but comes back on when plugged up..

My turn signal switch does not click when you flip it for the turn signal lights, will that affect anything?

I plan on replacing all 4 light sockets on the truck.

I am afraid its my steering column because its not original my truck is a 1985 diesel, I got the column out of a 1981 gas truck. Maybe wiring differences, Also my column use to be tilt and had cruise....

What opinions do you guys have? I would like to get a diagram of the U shaped plug in for a diesel if anyone has one....

 

As I read it, you have seperate strings going for your lights and for your horn which also doesn't work. You also state your directional switch doesn't seem to be working right. Both the horn and the lights work through the directioal switch that isn't working correctly. I'd change the directional switch. You sound nervous about the steering column, but this fix isn't any big deal. You need to disconnect the negative battery cable, pull the steering wheel, unscrew the directional lever from the switch, unplug that u-shaped connector you've refered to, and remove the two screws that hold the directional switch to the column. The whole switch including the wiring harness pulls right out from the column. As long as you have a steering wheel puller it's a thirty minute job if you stop for three beers.....it's that easy.

 

Forgot to add one last problem, after I did all my trial and error, when I turn on my passanger side turn signal the headlight buzzer buzzes now!!!! AHHHH im getting mad!

Where can I get a turn signal switch at? and how much?

 

You can get them at almost any parts store...NAPA's web site has the non-tilt switch at 48.99...Advance Auto's site has them as low as $39.99....I've seen them pretty available on Ebay also...just shop around.

 

You have a short between the parking lamp circut, and the turn signal circut.

Replace the corroded lamp socket first, and all obvious problems, then we can diagnose from there.

The 1981 collumn is the same, tilt, for tilt, etc... but the wiring inside is very different.

And with the cruise control equation, there is your other problems too. Do you still have the TS switch, and wiring from the 1985?

 

I replaced all the light sockets and replaced all the bulbs and waalaa problem fixed!!! Also the short between the parking lamp and turn signal was the front turn signal bulb which was all corroded. I replaced things and no problems.

I no longer have the TS switch or wiring from the tilt. After this problem I see no other problems, it was other things making the problems and not the column.

 

I had a feeling it would be one of the sockets or bulbs that was causing that problem. Very common problem with double filament bulbs actually.

glad things are coming together.