PCM Related Outputs
Coil PackA coil in a coil pack is cycled On by the Ignition Control Module (ICM), then cycled Off, firing two spark plugs at once. The spark plugs are paired so that as one spark plug fires on the compression stroke, the other spark plug fires on the exhaust stroke. The next time the coil is fired the order is reversed. The next pair of spark plugs fire according to the engine firing order.
Cooling Fan Control
Stand Alone Fan Control Relay Applications
The electric cooling fan is used in addition to the mechanical engine driven cooling fan. When additional cooling is desired, the Powertrain Control Module (PCM) will ground the Fan Control (FC) output. This will energize the Fan Control Relay coil and close the relay contacts, turning On the electric cooling fan.
Electronic Pressure Control Solenoid
The Electronic Pressure Control Solenoid (EPC) signal controls line pressure used to apply and release clutches and bands in the transmission.
Fuel Pump
The Fuel Pump (FP) output signal grounds the FP circuit connected to the coil of the Fuel Pump Relay for fuel pump operation.
Fuel Injectors
The PCM output signal that controls the solenoid operated valve to meter fuel flow to the engine.
Shift Solenoids
The Shift Solenoid 1 (SS1), Shift Solenoid 2 (SS2) and Shift Solenoid 3 (SS3) output driver signals to the transmission shift solenoids provide gear selection (first through fourth) by controlling transmission fluid pressure of the shift valves.
Transmission Control Indicator Lamp
The Transmission Control Indicator Lamp (TCIL) is an output signal from the PCM that controls the lamp On/Off function depending on the engagement or disengagement of overdrive.
Torque Converter Clutch Solenoid
The Torque Converter Clutch (TCC) Solenoid controls application, modulation and release of the transmission torque converter clutch.
Wide Open Throttle A/C Cutoff
The Wide Open Throttle Air Conditioning Cut-off (WAC) output is used by the PCM to disengage the A/C clutch when compressor operation is not desirable.