The EV Winnebago camper has an LED gauge panel over the fridge to show levels
of water, propane, and aux battery. The entire panel failed (no lights) as we
filled tanks for our first trip. I've now had a chance to find the cause, and
it looks likely that this problem will affect others, so here's a summary:

One etch trace on the back of the panel circuit board carries power from the
input connector at the rear end, along the full length of the lower edge of
the board to the switch connector at the front. This etch had melted through
at one spot, so no power went to the switch.

This etch line appears to carry current for the entire panel. As tanks are
filled and more LEDs light, this trace has to carry more current. It's a very
fine trace, and appears to be designed undersized for the current it has to
carry when most LEDs are lit. Of course it will heat more the longer you hold
the switch with the LEDs on. A dealer will certainly replace the board under
warranty, but it looks likely to happen to the replacement too.

The cure is to solder a "green-wire" jumper the full length of this trace,
from the diode terminal on one end to the switch socket on the other. Since
current divides through multiple traces on the rest of the board, this one
long trace is probably the only one that will cause problems.

Tom