Back half of trailer no lights

2015 Prowler Lynx

Front half of interior lights and front door exterior light works.

Memorial Day Weekend: Back half of interior lights, rear door exterior light do not work. My interior outlets are not working. The LED bar on the awning is very dim (acts like its on a dial and lowest setting). I checked breakers and fuses. All good.

7/1/23: Haven't taken camper out since Memorial Day Weekend, ran voltage tester to the switches for the lights in the back half of the trailer, no power. Breakers and fuses all good.

Where does a guy start? I have zero knowledge of electrical maintenance for travel trailers.

I do have an appointment for the camper to go into the dealer on 8/6, they acted like it'll be end of August by the time they can get to it. I need camper by Labor Day weekend (home opener vs TTU). I'm studying for the PMP exam which I hope to take end of July.
 

6.7LMegaCab

Well-known member
Sounds like a broken ground somewhere. You mentioned outlets - 12V outlets are inop or 120V outlets or both? My toy hauler didn't come equipped with any 12V outlets.

The dim awning lights could be a weak ground or you have weak batteries.

No fuses popped tell me there isn't a short.

The mechanical 12V breakers could have an appearance that they are fine. I had problems a few years back with them and mechanically appeared fine. Further troubleshooting showed a few were bad. Replaced all of them and no issues since.

If batteries aren't charging (assuming you have a converter charger), then it definitely could be a bad breaker and depending on how your trailer is wired, may just be causing other issues.

A quick way to see if the breakers are working would be to bypass the breaker to see if you get any lights back.

Sent from my SM-G781U using Tapatalk
 

6.7LMegaCab

Well-known member
Just a side note, this happens when running on battery power or plugged into the generator.
I would look closely at the grounds and/or isolate the 12V breakers. If they aren't working on generator or battery, it can't be much else, other than a 12V positive wire that's worked it's way loose, but hasn't made contact with the chassis.

Sent from my SM-G781U using Tapatalk
 

wdk450

Well-known member
These kind of wiring problems can be a real challenge. I am going to start off assuming that your problems are with the trailer's own 12 volt DC interior electrical system, and no problems with the stop, tail, marker lights or electric brakes powered by the truck. This interior system has 2 power sources - stored 12 volts DC in the battery and 12 volts DC derived from the 110 volts AC shorepower by the converter/charger. My first voltage testing device of choice would be a 12 volts DC incandescent light with a sharp probe like this: https://www.harborfreight.com/612v-circuit-tester-with-5-ft-lead-63603.html
Standard use of this tester is to connect the cable clip to a grounded metal item and use the probe point to probe for 12 volts to light the light. The best point to start with the clip is the negative terminal of the battery. Alternately, you can connect the clip to the Positive battery terminal to probe for good ground points and connections.
I would start with the rig plugged in to shorepower by disconnecting the positive cable from the battery, then probing that cable end with the clip on ground to test if the converter is supplying voltage. You could also do a quick probe of the disconnected positive battery terminal to see if it has voltage, but use the more reliable converter supply for testing. The rest of the testing will be from the voltage source (converter) towards the loads (lights, 12 volt devices). The test on the positive battery cable will tell you if the buss bar main charging breaker is tripped or not. All the smaller 12 vdc load current paths should be through the 12 volt fuse block. You can use the probe to touch metal fuse connectors on the fuse board. All of the connectors on the left side of each fuse should go directly to 12 volt power. All the connectors on the right side of the fuses should go to the individual loads. In the case of your major problems do not trust any built in indicators - trust only your test light or a DVM if yo know how to use one. If you truly have no voltage at the light switches (which are located just above the fusepanel in my rig) it means your possible wire breakage is between these 2 areas. If your rig was left in storage with these electricals working OK, then was found to have inoperative circuits before the next trip, I would suspect rodent damage to the wiring between the fusebox and the switchpanel.
Good luck!!!
 
Interior lights and rear porch light are working! Found my problem. The termination screw for black wire on the rack was loose so the wire was not having necessary contact. I did however check the remaining termination points and the yellow wires screw was slightly loose. As for the awning light bar, I'll have to wait till dark check, but at noon it appeared to be brighter.

My outlets are (interior and exterior) work when trailer is using shore power or generator, are these supposed to work when under battery power?
 

Attachments

  • IMG_9253.jpeg
    IMG_9253.jpeg
    1.5 MB · Views: 5

wdk450

Well-known member
The 110 volt outlets will not work without a source of 110 volt AC power; that is shorepower or generator. The generator should be all you need if you don't have AC shorepower. A DC to AC inverter to use battery power in your case would just be a waste of money.
 
Top