Thrush Aircraft S2R–T660 Maintenance Manual page 131

TROUBLE
Fuel indicated full at all times.
No fuel flow to engine-driven
fuel pump.
5 -13
THRUSH AIRCRAFT INC – T660 TURBO THRUSH
AIRCRAFT MAINTENANCE MANUAL
PROBABLE CAUSE
Loose connections or open
circuit.
Left and right fuel quantity
indicator switch defective.
No power to gauge.
Power, ground and
transmitter checks good.
Open ground between gauge
and transmitter.
Fuel tanks empty.
Check connections and wiring.
Tighten connections; repair or
replace wiring.
Check continuity and replace if
defective.
Check power to gauge. If no
power, check for defective
circuit breaker.
Circuit board on rear of gauge
defective. (Replace board) or
entire gauge.
Check ohms to transmitter.
Check for broken wire.
Transmitter should read 0
ohms when fuel tank is empty
and 33 ohms when fuel tank is
full.
Check fuel quantity. Service
with proper grade and amount
of fuel.
Effective: 12/17/03