TCM Inspection

TCM INSPECTION [JA5A-EL]

Caution: The TCM terminal voltages vary with changes in measuring and vehicle conditions. Always carry out a total inspection of the input and output systems, and the TCM to determine the cause of trouble. Otherwise, a mix-diagnosis could occur.

1. Measure the voltage at each terminal.
^ If any incorrect voltage is detected, inspect the related system(s), wiring harnesses and connector(s).

Terminal Voltage Table (Reference)

Part 1:

Part 2:

Part 3:

Part 4:

Note: Use the ground of terminals 1C and 1Y of the TCM when measuring terminal voltage, as an error may occur when connecting the negative circuit tester to ground.

Inspection Using an Oscilloscope (Reference)
Input/turbine speed sensor signal





TCM terminals
^ 1 N (+)-2F ( - )

Oscilloscope setting
^ 1 V/DIV (Y) 1 ms/DIV (X)

Vehicle condition
^ Turbine speed at 700 rpm, N position

Intermediate sensor signal





TCM terminals
^ 1K(+)-1X(-)

Oscilloscope setting
^ 4 V/DIV (Y) 0.2 ms/DIV (X)

Vehicle condition
^ Vehicle speed at 40 km/h (25 mph), 4GR

VSS signal





TCM terminals
^ 1 M (+)-1 V (-)

Oscilloscope setting
^ 4 WDIV (Y) 1 ms/DIV (X)

Vehicle condition
^ Vehicle speed at 40 km/h (25 mph)

Pressure control solenoid signal





TCM terminals
^ 2Y (+)-2P (-)

Oscilloscope setting
^ 5 V/DIV (Y) 5 ms/DIV (X)

Vehicle condition
^ Idle after warm-up

2-4 brake solenoid valve signal





TCM terminals
^ 2V (+)-2P (-)

Oscilloscope setting
^ 5 V/DIV (Y) 5 ms/DIV (X)

Vehicle condition
^ Idle after warm-up

High clutch solenoid valve signal





TCM terminals
^ 2U (+)-2P (-)

Oscilloscope setting
^ 5 V/DIV (Y) 5 ms/DIV (X)

Vehicle condition
^ Idle after warm-up

TCC solenoid valve signal (lock up off)





TCM terminals
^ 2S (+)-2P (-)

Oscilloscope setting
^ 5 V/DIV (Y) 5 ms/DIV (X)

Vehicle condition
^ Idle after warm-up

TCC solenoid valve signal (lock up on)





TCM terminals
^ 2S (+)-2P (-)

Oscilloscope setting
^ 5 V/DIV (Y) 5 ms/DIV (X)

Vehicle condition
^ Drive the vehicle with lock up