Torque Converter Operation Test

Torque Converter Clutch Operation Test
This test verifies that the torque converter clutch control system and the torque converter are operating properly. Perform the test as follows:
a. Connect tachometer to engine.
b. Bring engine to normal operating temperature by driving vehicle at highway speeds for approximately 15 minutes in OD range.
c. After normal operating temperature is reached maintain constant vehicle speed of about 80 km/h (50 mph) and tap brake pedal with the left foot.
d. Engine rpm should increase when brake pedal is tapped and decrease about five seconds after pedal is released. If this does not occur, refer to Torque Converter Operation Concerns in Diagnosis by Symptom Index.