Electronic Component Description: Notes
The transmission control module (TCM) is mounted behind the RF fender, between the wheelhouse and the dash panel, below the battery and connects directly to the engine wiring harness. A single 49-way connector is used to make the connection between the vehicle wiring and the TCM. The TCM is an electronic control module that receives input or provides output in order to control the operation of the 4L60 automatic transmission.
The TCM receives the following inputs from the engine control module (ECM):
- Engine speed and torque values
- Engine intake air temperature (IAT), accelerator pedal position (APP) information
- Engine coolant temperature (ECT)
- Kick-down request
- Traction control status
- Driver selected shift mode
- Air-conditioning (A/C) status
- Cruise control status
The ECM provides this data to the TCM through the controller area network (CAN). The CAN is a 2-wire communication connection between the 2 controllers.
Other TCM inputs are the following:
- Battery and ignition voltage
- Brake switch status
- Transmission manual shift shaft switch assembly
- Transmission fluid temperature (TFT)
- Transmission vehicle speed sensor (VSS)
The TCM provides the following outputs in order to control the automatic transmission:
- Shift solenoids to control transmission shifting
- TCC PWM solenoid operation controls the apply and release of the torque converter clutch ASM
- Pressure control solenoid (PCS) regulates transmission line pressure
Other TCM outputs provided to the ECM are the following:
- MIL illumination request
- Vehicle speed
- Transmission input speed
- Transmission fluid temperature
- Commanded gear status
- TCC status
- Torque reduction requests
- Manual shift shaft switch status