Intermittent 12V Electrical Issue

[MikeZ]

I've searched the forums for a similar issue, but could not find a thread. When trying to operate my electrical off of 12v trailer battery (battery is confirmed fully charged), it would work intermittently. Now becoming more Not working than working. When I plug into my tow vehicle (running) it also only works sporadically. Everything (fingers crossed) works when plugged into shore power. When it isn't working, nothing works! hitch, lights, etc. Any suggestions for troubleshooting would be appreciated. We have several vacations coming up and not looking forward to manually operating the hitch jack.

[eatmedic]

First thing I would do would be to clean the connections to the battery terminals. I use coke, a wire brush and scrub away. Also could be a dirty or loose ground connection.

[tacoma238ml]

check your battery connections for corrosion and check the wire block behind battery ,should be on the frame

[sourdough]

When you are plugged into shore power your converter is powering your DC stuff via the AC input along with the battery(s).

Sounds like, as has been mentioned, either a dirty or loose connection in the circuit from the battery through the various other connectors before it gets inside the trailer.

You don't give the age of the trailer or the battery but keep in mind a failing battery can do some weird stuff and a "fully charged" battery doesn't necessarily mean it's in top shape - just in case:)

Oh! And welcome to the forum!

[SC Dreamer]

I would also check wire connections. At my batteries, the wires would easily pull out of the crimp connectors by hand.

[MikeZ]

Thanks everyone!! The battery is less than a year old with clean terminals and it checks out fine with a multi meter. I will check the ground connection to the frame for corrosion. The trailer is a 2010 Keystone Passport.

[Canonman]

Sounds like the problem is somewhere between the battery and the main power distribution panel. A couple of suspect connections would be at the auto reset circuit breaker. There may be two of these depending on the TT model. Another possibility would be the battery disconnect switch (if equipped). Look for any irregularities or degradation and do a "tug test" on all connections and connectors.
Good luck and let us know what you find.

[sourdough]

Sounds like the problem is somewhere between the battery and the main power distribution panel. A couple of suspect connections would be at the auto reset circuit breaker. There may be two of these depending on the TT model. Another possibility would be the battery disconnect switch (if equipped). Look for any irregularities or degradation and do a "tug test" on all connections and connectors.
Good luck and let us know what you find.

Great catch!! 2010 model..I would double check that bypass switch. I just replaced mine for the exact reasons you are describing (totally forgot). On again, off again. I first checked it with a multi meter and found it wouldn't switch cleanly. Forgot to replace it (had the new one sitting in the barn) and it acted up again and went thru the trouble shooting AGAIN!! You could turn on the lights and have someone stay inside and see if they come on and off cleanly when you turn the switch instead of using the meter.

[MikeZ]

Where is the bypass switch?

[sourdough]

They are in various places. Mine is in the pass thru on the front wall behind the batteries up front (they're outside the wall). It's a little red toggle looking handle stuck in a hole. Mine has a surround around it that says "on" and "off" depending on the position of the switch.

[Canonman]

Ours is in the storage area as well. Not all models were equipped with them. It should be visible and not too hard to find.

[MikeZ]

I never did find the battery disconnect, but working my way down the electrical circuit with a multi meter I did find a slightly loose and rusted connection. Cleaned it up and tightened and now everything is working fine. Thanks for the suggestions!