TCM Inspection

TCM INSPECTION [FN4A-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 terminal 10 and 1P 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)

VSS signal





TCM terminals
^ 2P (+)-10 (-)

Oscilloscope setting
^ 1 V/DIV (Y), 10 ms/DIV (X), DC range

Vehicle condition
^ Drive the vehicle at approximately 10 km/h (6.2 mph)

Input/turbine speed sensor signal





TCM terminals
^ 21 (+)-10 (-)

Oscilloscope setting
^ 500 mV/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition
^ Idle after warm up (engine speed approximately 700 rpm, no load, P/S off, A/C off)

Pressure control solenoid signal





TCM terminals
^ 1E (+)- 1P (-)

Oscilloscope setting
^ 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition
^ Idle after warm up (engine speed approximately 700 rpm, no load, P/S off, A/C off) (+)

TCM terminals





^ 1G (+)- 1P (-)

Oscilloscope setting
^ 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition
^ Idle after warm up (engine speed approximately 700 rpm, no load, P/S off, A/C off)

Shift solenoid A control





TCM terminals
^ 1A (+)- 1P (-)

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

Vehicle condition
^ Idle after warm up (engine speed approximately 700 rpm, no load, P/S off, A/C off)

Shift solenoid B control





TCM terminals
^ 1B (+)- 1P (-)

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

Vehicle condition
^ Idle after warm up (engine speed approximately 700 rpm, no load, P/S off, A/C off)

Shift solenoid C control





TCM terminals
^ 1C (+)- 1P (-)

Oscilloscope setting
^ 5 WDIV (Y), 5 ms/DIV (X), DC range

Vehicle condition
^ Idle after warm up (engine speed approximately 700 rpm, no load, P/S off, A/C off)