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Control Module: Testing and Inspection

TRANSMISSION CONTROL MODULE (TCM) INSPECTION
1. Turn the ignition switch to the ON position, and inspect the TCM terminal voltage, referring to the Terminal Voltage Chart.
- If any TCM terminal voltage is incorrect, inspect the related input of output devices and wiring.
- If no problem is found, replace the TCM.

Note: Use the ground of terminal AP of the TCM when measuring terminal voltage as an error may occur when the negative (-) lead of the circuit tester is connected to ground.

Terminal Voltage Table (Reference Data)





1 of 4





2 of 4





3 of 4





4 of 4

Input/Output Pulse (Reference) input/turbine speed sensor





- Connecting terminal: W (+)-AP (-)
- Measuring device setting: 1 V/DIV (Y) 5 ms/DIV
- Measuring condition: Idle

Vehicle speed signal





- Connecting terminal: AC (+)-AP (-)
- Measuring device setting: lV/DIV (Y) 5ms/DIV (X)
- Measuring condition: Vehicle speed at 30 km/h (18.6 mph)

Output speed sensor Connecting terminal: AF (+)-AP (-)





- Measuring device setting: 1V/DIV (Y) 5ms/DIV (X)
- Measuring condition: Vehicle speed at 30 km/h (18.6 mph)

Engine speed signal





- Connecting terminal: AG (+)-AP (-)
- Measuring device setting: 2V/DIV (Y) 5 ms/DIV (X)
- Measuring condition: Idle