Engine and Driver Demands

The powertrain control module (PCM) (12A650) receives and sends electrical signals that are used to make the transmission more responsive to driver and vehicle needs.

The driver demands are transmitted to the powertrain control module through four components:

• Transmission range selector lever—The driver's demand for a particular gear range is translated into an electrical signal for the powertrain control module by the manual lever position (MLP) sensor.
• Accelerator pedal—The driver's demand for torque and acceleration are sent mechanically to the throttle body (9E926) on the engine. A throttle position sensor (TP sensor) (9B989) then translates this mechanical motion into an electrical signal and sends it to the powertrain control module.
• Brake pedal—A Brake On/Off (BOO) switch tells the powertrain control module when the brake is applied, indicating the driver demand to disengage the torque converter (7902).
• Transmission Control Switch—A momentary contact switch, located on the side of the transmission range selector that allows the driver to manually select three or four speed operation.