Solar jolt to trailer frame and trailer brake controller short

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.


New member
Jul 9, 2024
Okay that was a horrible title...I am a solar newbie and would appreciate some troubleshooting assistance.

I have a 2006 Surveyor 26 foot hybrid trailer. I replaced the stock 12V battery with 2 - 6V Rolls S-550 (428 AH) in series. I installed a solar panel with 265W of nominal maximum power. I have a charge controller from Azimuth Solar which is a MPPT 20A charge controller ( MPPT 20A Programmable Solar Charge Controller 12/24V with On-Board Dis )

My wiring goes from the solar panel to a fuse (MC4), to the charge controller and then directly to the batteries.

It seems like there is a charge getting to the frame of the trailer somehow. When I touch a metal surface I have a low level "buzz" shock. Also, when I am hooked up to my truck, the lights all work but the brake controller light doesn't come on. When I disconnect the solar panel the brake controller works. I am assuming I have a short somewhere or have hooked something up wrong despite it pretty much being "idiot proof". Anything that I am obviously missing.

Thank you

VegieCruiser in Canada
The voltage coming off a solar panel or the batteries you can't get a shock from if you tried, and being DC it wouldn't 'buzz'. Does your setup have an inverter? 120V direct or through leakage is certainly enough to feel and would 'buzz' so that's the first thing I would investigate. Do you have a voltmeter? Anything you're feeling current from you should be able to measure, and then start to be able to trace.

Can't comment about brake controllers, other than if you notice cause/effect of function when you connect/disconnect the panel, it certainly sounds like something's getting grounded or shorted that shouldn't be. And true to how things generally happen, it's caused by something seemingly unrelated you would otherwise never suspect. First question I would ask is has it always been like this or is it new? Corresponds to a recent repair, replacement, installation of something?

Mark B.
Albuquerque, NM
Thank you for the reply Mark!!. This problem has only presented itself since I installed the solar system. I do have an inverter that is connected to the batteries and to shore power.

I will see if I can get more information with a volt meter.

Hmmm...sounds familiar...

While replacing all of our Casita trailer OEM 120VAC 15A electrical receptacle outlets with 120VAC 20A AFIC/GFIC electrical receptacle outlets, we discovered that the electrical receptacle outlet in our microwave cabinet was dangerously miss-wired. Apparently, the ground wire was cut too short so Casita Travel Trailer didn't use it at all. Instead, Casita Travel Trailer just connected the outlet neutral screw to the outlet ground screw. Interestingly, while this results in this electrical receptacle outlet still testing as if properly wired, this wiring approach dangerously places 120VAC on the ground path when an appliance is plugged into this electrical receptacle outlet which could then cause an electrical shock and potentially death. Fortunately, our Casita trailer shell is fiberglass and is not metal which likely kept us from encountering this fate on our Casita trailer pickup trip.

This type of miss-wired electrical receptacle outlet is very difficult to detect without actually looking at the electrical receptacle outlet wiring. Anyhow, we corrected this Casita Travel Trailer quality control issue and we mention this for people's awareness. Again, “No Shock Zone RV Electrical Safety” by Michael Sokol is a great source of reliable information on this specific subject.

So... Any chance you may have recently misswired a 120VAC electrical receptacle outlets?

Gayle & Bob
Los Gatos Casita

Latest posts

Forum statistics

Latest member
Top Bottom