No Running Lights on Flagstaff Pop Up

[farmertin]

Hi there,
I have a 1998 Forest River Flagstaff Pop Up camper. The trailer light wiring on the tow vehicle works great.
When the running lights are off, the brake and turn signals on the trailer work.
When the running lights are on, the running lights, turn signals, and brakes do not work. If I take the running light bulb out and replace it with my meter, it reads -12.11 volts (the positive and negative are switched). When I put the bulb in, it reads no voltage across the running light bulb side.

Questions,
There are lights around the trailer, like on the side, front and rear, amber and red. Are all of them supposed to be lit when the running lights are on?

Is there circuitry between the trailer light plug and the light bulbs? Or is it supposed to be direct wiring from the plug to the bulbs?

Any ideas what to check next?

Thanks for your time

[rockfordroo]

Questions,
There are lights around the trailer, like on the side, front and rear, amber and red. Are all of them supposed to be lit when the running lights are on?

Yes, they should all be on with running lights on.


Is there circuitry between the trailer light plug and the light bulbs? Or is it supposed to be direct wiring from the plug to the bulbs?

Should just be wiring.

Any ideas what to check next?

Sounds to me like your ground may be bad. When you lose your ground, the power tries to go backwards through the wrong thing to another ground, hence why you may be seeing the polarity switched.

Your trailer brakes usually go to ground by a connection to the frame near the wheels, I believe. Usually the running lights grounds all connect together and get back to the ground at one point. Not sure where that might be on your popup.

Maybe others will have other suggestions.

Hybrids and TT's typically have a junction box under the trailer near the front, usually on the street side, where the 7-wire TV connector and battery wiring all runs through. But I know my Coleman popup didn't have that, so I don't know if yours will or not. You'll probably end up having to try to figure out where all the wiring runs by following it around the camper if you can. Look for loose or disconnected wires and wires that may be shorting to something.

[Too Tall]

12.1 volts is not enough. Check your grounding. IMO.

[Rich5117]

May not be trailer issue. Check your connector on the vehicle, had a similar problem on an explorer, the inside of the connector got corroded and would allow some things to function but when turning on lights was shorting out things, but not enough to blow fuses.

[Flybob]

Check both sides of the Bargman the contacts can get dirty from lack of use. Plug and unplug a few times to try to clean them. Sounds like high resistance ground.

[elind]

Check the ground connections on the taillights. Bad grounds at the lights will cause the power to jump around through other paths.

[edt]

Bad Ground

[Flybob]

What is your TV. If a passenger vehicle ( not a truck) did dealer add a trailer light controller? Some vehicles need an adapter to make a trailer work with their lighting system.

[jking46]

Thinking back a few years to our Palomino popup, I think the ground was a wire that came out of the trailer side of the 4 pin connector. It attached to the trailer front a frame with a metal screw. Again, as I remember, the wire can fray causing poor grounding. Hope it helps.

[rockfordroo]

Originally Posted by jking46

Thinking back a few years to our Palomino popup, I think the ground was a wire that came out of the trailer side of the 4 pin connector. It attached to the trailer front a frame with a metal screw. Again, as I remember, the wire can fray causing poor grounding. Hope it helps.

The ground wire you are describing is the ground wire that gets the current from the TT frame back to the TV. But remember that each light circuit needs it's own ground wire to the frame so the return current from the light can get to the frame, go through the frame to that wire that goes to the 4 pin, and then back to the TV. Given his symptoms, I don't think that wire is his problem, as it is common to ALL the circuits. Also, the hitch itself provides a pretty good ground path; the wire to the frame is just "extra."

(I was an Aviation Electrician in the Navy. They called us "one wires," because the lights, motors, solenoid valves, etc all had just one wire. All the devices were grounded to the air frame and therefore didn't need any ground wire. Our trailers aren't like that. Each circuit has a ground wire. They often hook several of them together and then run ONE wire back to the frame somewhere. For example, the ground wires of the left running light, left turn signal, and left rear and side clearance lights (if you have them - probably not on a PUP) are all probably tied together and one wire from them goes to the frame somewhere. This is what causes these issues and makes finding this kind of problem difficult.)

[tmsimmons56]

just had that problem, to check for grounding issue use a jumper cable and ground your trailer to your truck. In my case the fuse was blown... New truck too.

Any ideas what to check next?

Thanks for your time[/QUOTE]