2500 4x4 Pickup L6-359 5.9L DSL Turbo (1995)
Fuel Cut Solenoid: Description and Operation
NOTE: The fuel shutdown solenoid and the fuel shutdown solenoid relay are not controlled by the powertrain control module (PCM).
PURPOSE:
The fuel shutdown solenoid is used to electrically shut off the diesel fuel supply to the high pressure fuel injection pump.
Fuel Shutdown Solenoid Positions
The solenoid controls starting and stopping of the engine regardless of the position of the accelerator pedal. When the ignition switch is off, the
solenoid plunger is spring loaded (down) in the shutdown position and the fuel is shut off to the injection pump.
OPERATION
Two different coils are located within the solenoid and a three-wire pigtail wire harness is attached to the solenoid.
When the ignition switch is turned to the CRANK (starter engaged) position, high amperage current (approximately 40 amps at 12 volts) is
supplied to one of the coils in the shutdown solenoid from the fuel shutdown solenoid relay. This high-amperage current allows the solenoid shaft
to pull up on the injection pump lever. The injection pump shutdown lever is then positioned to the run position.
When the ignition key is released to the ON position, a low amperage current is supplied to the other coil in the solenoid. This is used to hold the
solenoid shaft in the up position. Accelerator pedal position then controls fuel lever position for the fuel control at the injection pump.
Fuel Heater Relay
Voltage to operate the solenoid is supplied from the ignition switch and through the fuel shutdown solenoid relay.