Electrical issues ..Please Help!!

Indeed...

If everything works when the 7-pin is connected, then there is no problem with the "kill" switch or the fuses on the output side of the converter.

It is either the in-line battery fuse or a dead battery.

New last year just means it would take a couple of months sitting in a discharged state to be killed. Flooded cell batteries must be kept a fully charged!
-Charge it before leaving on a trip.
-Charge it upon returning from a trip.
-Charge it once a month when not being used.
-Disconnect the battery to prevent discharge from parasitic loads like the propane detector.

No one seems to have mentioned the Trailer Fuse next to the battery. It might be burned out. There should also be fuses at the Converter/Inverter for the 12 volt side as well as the circuit breakers at the 120 volt side. I would start there then progress to the cut out switch as mentioned on the rollover sink.

Frank

A handy VOLTMETER goes along way here - They are inexpensive here $7 to $20.


Since we camp alot off the power grid I look at my batteries using a DC VOLTMETER on a pretty good schedule. I also check my battery fluids on a regular basis as well. This is real important if you only have a single stage constant voltage converter/charger unit. These will tend to boil out your battery fluids when connected to shore power for long periods of time. Using smart mode converter/chargers helps solve this problem

Like stated above a fully charged battery will read 12.7VDC across the terminals when measured not connected to shore power. When you connect to shore power it will 13.6VDC read at these same terminals telling you your converter/charger unit is working and all fuses are good between the converter and the battery.

Like mentioned above my OFF-ROAD POPUP trailer also has a Ceiling Light disconnect plunger type switch that will disconnect 12VDC power from the ceiling lights when my fold-over sink/stove cabinet is folder over for travel. In my trailer however this only disconnects the ceiling lights and should not keep your battery from being charged.


The weight of the fold-over sink/stove top presses down on this switch assembly when setup for camping. My plunger switch is located in the bottom right side of this fold over cabinet photo mounted to the bottom cabinet setup.


I suspect you are going to find your trailer battery is discharged.

I also get a small trickle type charge from my truck battery when connected to my 7-pin trailer connector but this would take a very long connection period to fully charge my batteries with the truck motor running.

Just some of my thoughts

Just like in the old US western days you got to take care of the horse first. Its your only way to get back home haha...

Roy Ken

Agree on the battery, if hooking up gives you 12 v is there any power after you arrive at camp and unplug from the truck?

My guess is you have a dead battery. What voltage does it read? should be 12.7 volts for a fully charged battery. So use your volt meter and check and report back what you find and you will get more help after that. When you hooked up the 7way from the tow vehicle you were running off of the Tow vehicle battery and things worked from that fully charged battery. Things did not work from your RV battery because it is probably dead. They don't stay charged all year and you need to plug into shore power to recharge the battery. Report back what you find about battery voltage.

You replaced the battery last year? When is the last time you fully charged it up? Batteries go dead with use, and will go dead just sitting. You must be diligent in keeping it charged or it will not perform.

Safety switch was my first thought, as well... on our PUP, it's beneath the sink, which folds up into position when we're popped-up. If the sink isn't in its place, the safety switch holds the 12V circuit open so that nothing runs, especially the water pump. I honestly don't know if hooking the PUP up to the tow vehicle would defeat that switch... it doesn't seem like it should.

If you have a safety switch on the galley or somewhere else inside, that is the first thing I would check. I had to replace the one on ours when it went bad and it prevented the 12V system from working at all. It is designed to disconnect the 12V lights when you close up to be sure a light doesn't come on or get left on and burn the canvas.

If you don't have a switch or it checks ok, I would start looking for ground wires.