B Series Truck 2WD L4-2184cc 2.2L 2200 2-bbl (1990)
Fuel Pump Relay: Description and Operation
Circuit Opening Relay
The Circuit Opening Relay is an ECU controlled component of the fuel system. In response to the rpm (Ne) signal from the distributor, the ECU
energizes the relay when the engine is either cranking or running. The relay in turn supplies operating voltage to the electric fuel pump. As a safety
feature, the relay is not energized and the fuel pump does not run if the ignition is "ON" but the engine is not running or being cranked by the starter
motor.
