Torque Converter Operation Test

This test verifies that the torque converter clutch control system and the torque converter are operating properly.
1. Perform the Quick Test as outlined. Check for Diagnostic Trouble Codes (DTCs) P0741, P1741, P0743, P1742, P1743, P1744, P1767 and P1740; refer to Pinpoint Test C for diagnosis.
2. Connect a tachometer to the engine.
3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in (OD) position.
4. After normal operating temperature is reached, maintain a constant vehicle speed of about 80 km/h (50 mph) and tap the brake pedal with the left foot.
5. Engine rpm should increase when the brake pedal is tapped, and decrease about five seconds after the pedal is released. If this does not occur, refer to Diagnosis By Symptom.
6. If the vehicle stalls in (OD) or D at idle with the vehicle at a stop, move the gearshift lever to the L position. If the vehicle stalls, refer to Diagnosis By Symptom. Repair as required. If the vehicle does not stall in (OD), refer to Pinpoint Test C.