Dash lights blacking out when camper lights go on?

[alvald83]

I am having a problem with the circuit beaker going out and knocking out my dash lights at the same time. This happens when i have the camper connected to the truck via the original camper wire harness. My camper does have 14 running lights on it (original -non LED).
When i first turn the lights on, they'll run for about 5 minutes before it starts tripping the breaker. I look like a christmas tree going down the road. My plan is to install a relay somewhere near my camper plug and that should solve it, but i still want to replace that relay.
My question....Where is that relay? the clicking noise is coming from the glove box area. Will this be a hard part to find?

[knightfire83]

Depends how the camper lights are wired.

Scenario #1:
The relay and circuit breaker you speak of is located rearward of the passenger side vent, just right under the dash. This relay is typically used for trailer lights (at least on my '70 it was.) Some use it for clearance lights on top the cab.

The operation of the relay / circuit breaker should not interfere with the dash lights. As you see in the diagram below, the dash lights and the relay coil is powered by the headlight switch thru a fuse. If the relay's independent circuit breaker trips, it would not effect the coil side in the relay, thus not effecting the dash lights.

You would still hear the relay clicking on and off, as this happens normally when the dash lights are either turned on or off anyways regardless of what is connected to the relay, if anything. (Normal)

If your camper lights are in fact using this relay for power, and you have dash light problems, I would suspect the headlight switch first. The dash illumination fuse is apparently fine as you still have dash lights.... intermittently.

Scenario #2:
Your camper lights are directly connected to your dash lights, overloading the circuit. This would normally blow the fuse, however not if someone put a bigger fuse or aftermarket circuit breaker in the fuse box. Still, I would suspect the headlight switch or bad connections around that area. It could be too much load for the headlight switch tripping the internal circuit breaker, of which there is two... one for the headlights and one for everything else. In this case you will need to run a relay for your camper lights.

You may just have to trace back the power wire to the camper lights and see where in fact it leads to. Troubleshooting from there shout be pretty straight forward.

[basketcase0302]

Did you ever take some of the load off of it like suggested here:
http://www.fordification.com/forum/view ... 38#p618538

[alvald83]

I tried to bypass the problem by wiring my camper tail lights directly to the camper with the same blacking out light problem. I am going to replace the headlight switch to see if that corrects the problem. I am lost.

[basketcase0302]

alvald83 on Fri Nov 09, 2012 9:21 pm
I tried to bypass the problem by wiring my camper tail lights directly to the camper with the same blacking out light problem. I am going to replace the headlight switch to see if that corrects the problem. I am lost.

Did you ever take some of the load off of it like suggested here:
http://www.fordification.com/forum/view ... 38#p618538

[alvald83]

No not yet. Is there a possibility that it is the light switch itself. I figure, even though it cost a little bit, i'll try that first. The problem i am having is the time to go through and replace every light again with LEDs, but that is my next step.

[basketcase0302]

alvald83 on Sat Nov 10, 2012 11:00 am
No not yet. Is there a possibility that it is the light switch itself. I figure, even though it cost a little bit, i'll try that first. The problem i am having is the time to go through and replace every light again with LEDs, but that is my next step.

Yes there is a slim possibility that the switch is as fault and tripping our on overload-very slim IMO. You have to remember that you have quadrupled the load on your existing wiring circuit and switch by adding all the slide in camper running lights, (how many about 8-12)? It's a wonder IMO your trucks wiring hasn't melted down or isn't constantly blowing fuses.

[alvald83]

I guess what i could do it to install a new wire harness and switch for the clearance lights and run just the tail lights from the trucks tail lights.