Help needed backup circuit on 30P?

[pbsled]

I am putting in new backup lights that will be run by a relay on a fresh fused circuit. Lights and relay are okay since they will run lights if relay is latched with 12V

I located the backup circuit wire (yellow at taillight) through process of elimination. All other lights work fine if triggered by 7 pin harness at switch. However if I trigger backup circuit at the 7 pin - no workie. No 12v at rear of camper where I am picking up the latch circuit feed.

Does anyone know if there is a fusable link or online fuse somewhere on that backup light / aux circuit in a 30p or similar 80s gen Avion?

Many thanks ..... very busy weekend with sorting electrical issues.

[Razorback]

Attaching a page out of the owners manual from our 1987 34W. It shows the exterior 12VDC circuits. You'll see that the back-up lights are, indeed, on the yellow wire. You'll also see that there is no indication of anything but straight wire from front to rear. I am guessing that there is some corrosion or a break in that circuit somewhere, causing enough resistance to drop or lose the voltage by the time it gets to the end of the trailer.

Hopefully your 1990 model is somewhere close to this.

(Speaking of that...... does anyone have a 1990 Owners Manual that we can add to our Documentation section?)

[pbsled]

Thanks, and that is very helpful indeed. I went ahead and put in a manual switch to hold the relay as needed until I get that sorted. Based on that diagram I think I will defer a real fix (fresh home run to plug) until later.

[Razorback]

Thanks, and that is very helpful indeed. I went ahead and put in a manual switch to hold the relay as needed until I get that sorted. Based on that diagram I think I will defer a real fix (fresh home run to plug) until later.

We have a 1981 Ford Bronco. A common problem on all of the Broncos is with the power rear window. Maybe fresh from the factory it worked fine, but over time it seems that they all get weak or quit working altogether due to the voltage dropping by the time it gets to the rear window motor. It just doesn't have enough ooomph to push the window up, but the motor is just fine.
I will be installing a couple of 12V rechargeable batteries that I can power the window with, triggered and held through a relay like you are talking about. I cannot WAIT to get that project finished.

[Salty]

on my 34V up front underneath, there is an access panel in the belly pan where the whip meets the trailer wiring for the running light. Does a 30P not have one? Could there be a corrosion issue there?

[pbsled]

I will check for an access panel. Thanks for the tip.

[silverloaf]

Our '88 30P has the access panel. It is located at the front of the belly pan, adjacent to the rigid propane supply line.

I, too, had conductivity issues with the yellow wire. Our trailer had an unused purple wire that ran from the tail light housing to the access panel. I cut the yellow wire at both ends and grafted in the purple.
The work is shown in the attached pics.

I have yet to chase down why the trailer running and clearance light circuit is blowing the dedicated 25A fuse in the truck. Everything worked a year ago after replacing the tail light assys and clearance lights. Unfortunately, I ran out of time to chase it down and must travel to Georgia today without them. Fortunately, my wife will be following me (we're moving there) and I won't be driving at night.