Driving down the road, in the rain, both the coolant temp gauge and
fuel tank gauge go to zero. Can't say they did it at the same time
because sometimes I need to look where I am going. Coolant tanks are
both fine and I know I have at least a half a tank of fuel. Everything
else on the dash seems to work (cat converter, oil pressure, etc).
Fuses look good but I looked pretty quick.  The main harness is
plugged in behind the dash.   When I turn the key to on but don't
start the engine the coolant temp light  blinks forever but it's
pretty faint.  When I start the engine sometimes the coolant blinks
for the three seconds, other times it never blinks. The rest of the
lights on the dash are bright. What's the deal? 1984 Vanagon GL