FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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FNR5 - Automatic Transaxle

Torque Converter Diagnosis

Special Tool(s):





Prior to installing a new torque converter, all diagnostic procedures must be followed. This is to prevent the unnecessary installation of new or remanufactured torque converters. Only after a complete diagnostic evaluation can the decision be made to install a new torque converter.

Begin with the normal diagnostic procedures as follows:

1. Preliminary Inspection.
2. Know and Understand the Customer Concern.
3. Verify the Concern - Carry out the Torque Converter Clutch Operation Test; refer to Torque Converter Operation Test.
4. Carry out Diagnostic Procedures.
^ Run on-board diagnostics; refer to On-Board Diagnostics With Scan Tool. FNR5 - Automatic Transaxle
- Repair all non-transaxle related DTCs first.
- Repair all transaxle DTCs.
- Rerun on-board diagnostic to verify repair.
^ Carry out the Line Pressure Test. Refer to Line Pressure Test. FNR5 - Automatic Transaxle
^ Carry out the Stall Speed Test. Refer to Stall Speed Test. FNR5 - Automatic Transaxle
^ Carry out the Diagnosis by Symptom Index. Refer to Diagnosis By Symptom. FNR5 - Automatic Transaxle
- Use the index to locate the appropriate routine that best describes the symptom(s). The routine will list all possible components that may cause or contribute to the symptom. Check each component listed; diagnose and repair as necessary before installing a new or remanufactured torque converter.

Torque Converter Operations Test
This test verifies that the torque converter clutch control system and the torque converter are operating correctly.

1. Carry out the Self Test. Refer to On-Board Diagnostics With Scan Tool. Check for DTCs. Refer to Diagnostic Trouble Code (DTC) Charts. FNR5 - Automatic Transaxle FNR5 Automatic Transaxle/Transmission
2. Connect a scan tool.
3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in D 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. The engine rpm should increase when brake pedal is tapped, and decrease about 5 seconds after pedal is released. If this does not occur, see Torque Converter Operation Concerns. Refer to Diagnosis By Symptom. FNR5 - Automatic Transaxle
6. If the vehicle stalls in D at idle with vehicle at a stop, move the position selector lever to L position. If the vehicle stalls, refer to Torque Converter Operation Concerns. Repair as necessary. If the vehicle does not stall in D position. Refer to Diagnosis By Symptom. Torque Converter Clutch Operation Concerns 240/340 - 242/342 FNR5 - Automatic Transaxle