Transmission Control System

Powertrain Control Module:

Transmission Control Electrical Components (4L80E):

Data Link Connector (DLC):

DESCRIPTION
The Transmission Control Module (TCM) is an electronic device which monitors various inputs to control various transmission functions including shift quality and transmission diagnostics. The TCM receives various input information from sensors, switches, and components to process for use within its control program. Based on this input information, the TCM controls various transmission output functions and devices. The TCM is located within the passenger compartment, underneath the right hand side of the dash.

INPUT INFORMATION
The TCM uses the following information sensors to gather data for electronically controlling transmission functions.

^ Transmission Fluid Temperature (TFT) sensor.
^ Transmission Range (TR) pressure switch assembly.
^ Engine Coolant Temperature (ECT) sensor.
^ Accelerator Pedal Position (APP) module.
^ Transmission Vehicle Speed Sensor (VSS).
^ Brake Switch.
^ Input Speed Sensor.

OUTPUT INFORMATION
Based on the input information, the TCM controls various transmission output functions and devices.

^ 1-2 Shift Solenoid.
^ 2-3 Shift Solenoid.
^ Pressure Control Solenoid (PCS).
^ Torque Converter Clutch (TCC)Pulse Width Modulation (PWM) Solenoid.