TCM Function

The function of the TCM is to:

Receive input signals transmitted from various switches and sensors.
Determine required line pressure, shifting point, lock-up operation, engine brake operation, etc.
Transmit required output signals to the respective solenoids.

SENSORS (or SIGNALS)	=>	TCM	=>	ACTUATORS
Transmission range switch Accelerator pedal position signal Closed throttle position signal Wide open throttle position signal Engine speed signal A/T fluid temperature sensor Output speed sensor Vehicle speed signal Manual mode switch signal Stop lamp switch signal Input speed sensor ATF pressure switch Tow mode switch	=>	Shift control Line pressure control Lock-up control Engine brake control Timing control Fail-safe control Self-diagnosis CONSULT communication line Duet-EA control CAN system	=>	Input clutch solenoid valve Direct clutch solenoid valve Front brake solenoid valve High and low reverse clutch solenoid valve Low coast brake solenoid valve Torque converter clutch solenoid valve Line pressure solenoid valve A/T CHECK indicator lamp A/T fluid temperature warning lamp Tow mode indicator lamp Back-up lamp relay Starter relay

INPUT/OUTPUT SIGNAL OF TCM

Control item

Line pressure control

Vehicle speed control

Shift control

Lock-up control

Engine brake control

Fail-safe function⁽³⁾

Self-diagnostics function

Input

Accelerator pedal position signal ⁽⁵⁾

Output speed sensor

Vehicle speed signal ⁽¹⁾, ⁽⁵⁾

Closed throttle position signal ⁽⁵⁾

X⁽²⁾

X⁽⁴⁾

Wide open throttle position signal⁽⁵⁾

X⁽⁴⁾

Input speed sensor 1

Input speed sensor (for 4th speed only)

Engine speed signals⁽⁵⁾

Stop lamp switch signal⁽⁵⁾

X⁽⁴⁾

A/T fluid temperature sensors

ASCD or ICC sensor integrated unit

Operation signal⁽⁵⁾

Overdrive cancel signal⁽⁵⁾

Output

Direct clutch solenoid

Input clutch solenoid

High and low reverse clutch solenoid

Front brake solenoid

Low coast brake solenoid (ATF pressure switch 2)

Line pressure solenoid

TCC solenoid

A/T CHECK indicator lamp⁽⁶⁾

X⁽⁴⁾

Starter relay

⁽¹⁾	Spare for output speed sensor

⁽²⁾	Spare for accelerator pedal position signal

⁽³⁾	If these input and output signals are different, the TCM triggers the fail-safe function.

⁽⁴⁾	Used as a condition for starting self-diagnostics; if self-diagnostics are not started, it is judged that there is some kind of error.

⁽⁵⁾	Input by CAN communications.

⁽⁶⁾	Output by CAN communications.