I think Sun Roper has a bad DC-DC converter.

This morning when I tried to drive SR it would not go and the odometer
display would go on and off, sometimes a few times and then stay off.
After fiddling with several things, including charging the aux battery
with an standard charger since it was low, now the low-battery light
comes on (the batteries show fully charged according to PakTrakr) and
the forward contactor chatters like mad when I put the selector in F.
Once I was able to get chatter when I put the selector in R and
pressed the REVERSE button, but other times not.

Could this be because of a bad DC-DC converter? I have the old-type
DCDCC with moisture protection applied. I was able to unplug the black
connectors coming out of the DCDCC to check for a short (it wasn't). I
could not get the gray connector unplugged by pressing on the obvious
tab to press; is there a secret to doing that?

If not the DCDCC, what could be the problem?

Dave Roper