Pop up camper wiring confusion.

[Stoof]

1. What are the blue wire and quick disconnect for?
2. There's only 3 wires hooked to the 4 pin?
3. All the lights except running lights work. Obviously could be part of question 2.

Thanks.

[DCT]

Not sure on #1 could you trace them to see where they go?
#2 the white wire that's cut short is the ground wire. Some people don't hook it up and just count on it grounding through the trailer ball.

[hunter1313]

The quick disconnect is battery connections for the lights on the inside of the camper. Blue wire most of the time is brakes.

[JustinJ]

Blue should be a brake wire. White and black on the quick disconnect could be for back up lights and 12v power, but maybe not because of the quick disconnect. You need to buy a new plug even if you keep the flat 4 because you need to use the 4th (white) wire to ground the trailer, otherwise your lights will flickers going down the road. DONT GROUND OFF THE BALL. Looks like someone just wanted to make the lights work for the time being

[hellbndr23]

My guess is blue wire for brakes and the quick plug was the emergency battery backup / disconnect for the brakes. Someone only had a 4 pin on their truck and wanted to move it. Cut everything else off.

[Stoof]

Thanks y'all. What about the running light issue?

[Shake N' Bake]

I have a Coleman pop up and have the exact same white/black with quick connect and I could figure out what it was for.

[careybirdwell]

Your running lights might not be getting a good ground because your white wire is disconnected or you have a bad connection on your brown wire

[huntinfool]

Blue is brake.
Two problems could exist. No ground may be the cause of the tail lights not working. Or it could be something else. Have you checked the fuse on the truck?
I guess the plug itself could be bad. That could also keep the taillights from working.
Use a test light or a multi meter to check the truck. If it's good, then start with a new plug and ground the wire to the frame of the trailer.

[Robertt]

I didn't see what make and model you have. We have a Jayco and it needs a special adapter to the four wire connector off the truck for the lights to work correctly. I have a heavy brake wire on mine but no trailer brakes. I got the adapter at etrailer.com.

Gave new meaning to two wrongs don't make a right but three lefts do.

[hellbndr23]

Thanks y'all. What about the running light issue?

Get a new 4 prong plug and find the ground wire in that nice loom below the tape. 90% of the time light issues are a bad ground. I run a ground wire to every light. Avoid using the trailer and ball as a ground at all costs.

[Uncle Saggy]

Get a new 4 prong plug and find the ground wire in that nice loom below the tape. 90% of the time light issues are a bad ground. I run a ground wire to every light. Avoid using the trailer and ball as a ground at all costs.

Good advice