Viper V10-488 8.0L (1992)
Main Relay (Computer/Fuel System): Description and Operation
Fuel Pump Relay
Fuel Pump Relay
FUNCTION
Relay supplies battery voltage to fuel pump and oxygen sensor heater element when energized by PCM.
OPERATION
The Powertrain Control Module (PCM) energizes fuel pump relay by supplying relay ground, when ignition switch is in START or RUN position
and PCM is receiving a reference signal from distributor.
When PCM does not receive reference signal from ignition system, (indicating engine is not running), then the PCM interrupts relay ground circuit
and no voltage is supplied to fuel pump, ignition coil, or oxygen sensor heater element.
PCM controls fuel pump relay and Auto Shutdown (ASD) relay simultaneously, through same ground circuit.