No power from tow vehicle

[U771663]

I have a 2017 sunset trail and when plugged into shore power everything works fine. When plugged into tow vehicle all the trailer lights work but I have no power inside the camper. Nothing works. Green 30 Amp fuse going to power jack is good, all fuses inside camper are good. Breakers are good. Any ideas?

[dagst1]

When you unplug the shore power you have no power inside the camper do you mean the outlets do not work or the lights do not work? There is 2 separate systems the 12 volt that runs things like the lights and water pump for a few and the 120 volt that runs your outlets.

[660catman]

You need to determine if your tow vehicle has 12v constant at #4 pin. Some trucks may not.

https://www.etrailer.com/question-363.html

[U771663]

Originally Posted by 660catman

You need to determine if your tow vehicle has 12v constant at #4 pin. Some trucks may not.

https://www.etrailer.com/question-363.html

This just started.

[U771663]

Originally Posted by dagst1

When you unplug the shore power you have no power inside the camper do you mean the outlets do not work or the lights do not work? There is 2 separate systems the 12 volt that runs things like the lights and water pump for a few and the 120 volt that runs your outlets.

The 12v system. This just started. The battery is completely shot. Hoping a new battery will correct this. But I would think it would still run the 12v inside and the jack

[dagst1]

Not sure on your truck but do you have 12 volt to the plug with the motor off? Also have you checked the truck plug for power? You are correct the truck would supply 12 volt to the camper so first check the plug.

[mark5w]

An RV converter will continue to work even without a battery in place as long as you are plugged into shore power.

[dagst1]

I take it that the converter is good as he states when plugged into shore power everything works. The part I am confused about is when plugged into the truck all the trailer lights work but no power on the inside. So are you saying the outside trailer lights -- tail, running/clearance and brake work. But you have no lights inside the camper. Also your battery is dead. And the outlets would not work as they are 120 volt.

The first place to start would be the truck plug. If you have power there it is on the trailer side but if not it is on the truck side. It will give you a direction to go.

[gespringer1]

Tow vehicle line to the camper may have it's own fuse.

[DannyZeee]

Originally Posted by U771663

I have a 2017 sunset trail and when plugged into shore power everything works fine. When plugged into tow vehicle all the trailer lights work but I have no power inside the camper. Nothing works. Green 30 Amp fuse going to power jack is good, all fuses inside camper are good. Breakers are good. Any ideas?

I have a 2018 Crossroads Sunset Trail 253RB. It came with a white wire (#8 or #10, with 1/2" of insulation stripped off the end) hanging from the loom on the hitch. I was concerned what it might be, so checked it for voltage, resistance to ground, resistance to 12V+, nothing, it didn't seem to be connected to anything, so I didn't worry about it.

Then one day when I was hooking up the truck, I bumped this wire, and it arced to the frame. Turns out, it is the power from my truck, that is supposed to keep the battery charged going down the road, and was never connected. It seems it has a relay (likely at the converter) to disconnect the output to the truck when the camper is on shore power. Now it is hooked to the battery, & I no longer have a dead battery when I get where I am going.

It also could have potentially damaged my truck if ot had shorted to the frame and I hadn't noticed it.