I'm renovating an '80's circa slide-in, pop-top Skamper. With a lot of help from DWH, I've rewired the bus bar and other stuff. However, after having done all that, it doesn't appear the converter is working. The 12V items (lights, 12V accessory outlet, and water pump), only work when the battery is connected, i.e., when the power center switch is flipped to "Converter," rather than "Battery," the 12V stuff works IF the battery is connected but not when it isn't connected. The lights work off shore power or battery, being slightly brighter when running off shore power. Note that the 12V wiring for the lighting comes directly off the power center, whereas the other 12V stuff is connected through the bus bar that's connected to the converter by a wire adjacent to the 12V lighting and furnace power cables.
I'd appreciate help in figuring out how to identify the problem.
Here are photos of the original wiring mess, and the re-wired bus bar. From top to bottom, the wires from the bus bar go to the converter, a 12V water pump, and a 12V accessory outlet.
Bus bar.jpg Rewired bus bar.jpg
The front of the Power Center has a switch on the left side. Flipping the switch to the left is for shore power use and should engage the converter. Flipping it to the right is for battery power. Off is in the middle. There's a fuse on the left. On the right is a green indicator light that doesn't work (it appears to be physically broken) and a 120V outlet.
Front of Power Center.jpg
The back of the cover plate shows the wiring diagram for the power center.
Here are pictures of the 12V and 120V sides of the power center.
12V side.jpg 120V side.jpg
When I put a multimeter on the 12V terminals on the power center, it reads 12V only from the terminal on the far left which corresponds to the "converter" side of the switch. I get no reading on the middle terminal which connects to the fuse and corresponds to the off position of the switch, or the right-side terminal which corresponds to the "battery" side of the switch. I put in a new 30A fuse and still got no reading. There's no corrosion in evidence. Not surprisingly, when the battery's not connected, I get no reading off the bus bar. When it is connected to the battery, everything reads about 9V on both sides of the fuses and the bus bar.
And here's the back of the power center.
Power Center diagram.pdf
Could the problem just be a bad switch?
Thanks for any help you can give.