Torque Converter Clutch: Testing and Inspection

This test verifies that the torque converter clutch control system and the torque converter are operating properly. Perform the test as follows:
1. Perform On-Board Diagnostic Quick Tests. If Diagnostic Trouble Code (DTC) P0741 or PO743 "Torque Converter failures "appear, follow appropriate pinpoint tests or diagnostic procedure.
2. Connect a tachometer to the engine.
3. Bring engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in D position.
4. After normal operating temperatures are 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 brake pedal is released. If this does not occur, then torque converter operational tests will be necessary.
6. If the vehicle stalls in D at idle with the vehicle at a stop, move the transaxle range selector lever to the manual 1 position. If the vehicle stalls, the cause may be the converter control valve in the pump. Service as required. If the vehicle does not stall in manual 1, refer to Pinpoint Test C. Pinpoint Tests
7. Perform visual inspection.
8. After a road test, with the vehicle warm and before disturbing any connectors, perform the Quick Test using Rotunda New Generation Star (NGS) Tester 007-00500 or equivalent.
9. Review all technical service bulletins which pertain to the transaxle concern and follow the procedures.