P0741-TORQUE CONVERTER CLUTCH CIRCUIT PERFORMANCE
Theory of Operation
The Transmission Control Module (TCM) monitors the Torque Convertor Clutch for slippage using a calculation derived from turbine revolution (input speed) and engine rpm broadcast over the CAN C BUS. If the slip value exceeds a predetermined value the DTC will set.
- When Monitored:
Ignition on, engine running with the transmission in a valid forward gear.
System voltage between 9.0 and 16.0 volts.
Vehicle speed greater than 10 Km/h (6 mph).
Accelerator Pedal Position (APP) greater than 12.5%.
Engine rpm greater than 450 rpm with TCC lock-up enabled.
TCC Lock up command is ON (True).
No active DTCs from the following:
- Step motor,
- Line Pressure Solenoid
- Secondary Solenoid
- Input or Output Speed Sensor
- Primary or Secondary Pressure Sensor
- CAN Bus
- Set Condition:
The DTC is detected If the Torque Convertor Clutch (TCC) slip monitored by the Transmission Control Module (TCM) is greater than a predetermined value for the period of 30 seconds. Note: This is not an electrical fault but a mechanical malfunction such as a control valve sticking in its bore or a TCC Solenoid hydraulic malfunction. It takes two consecutive problem identification trips for the DTC to mature and illuminate the MIL.
| Possible Causes |
| TORQUE CONVERTOR HYDRAULIC CIRCUIT |
| TORQUE CONVERTOR CLUTCH SOLENOID |
| TORQUE CONVERTOR CLUTCH |
| TRANSMISSION CONTROL MODULE |
Always perform the CVT Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)
Diagnostic Test
1. CHECK TO SEE IF THE DTC IS ACTIVEWith the scan tool, erase Transmission DTCs.
Start the vehicle and check Transmission Fluid Level per the Service Information and adjust as necessary.
Test drive the vehicle to a constant speed greater than 40 Km/h (25 mph) for the period of at least 30 seconds.
NOTE: This can not be performed on a hoist, actual road conditions must be present for proper results.
Did the DTC reset (one trip) during the road test?
Yes
- Replace or repair the CV Transmission as necessary. Note the components related to the Torque Converter Clutch (TCC) such as the TCC Solenoid, control valves, valve body leakage or the TCC. Refer to the Service Information.
- Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)
No
- Go To 2
2. INTERMITTENT CONDITION
The conditions necessary to set this DTC are not present at this time.
Refer to an Technical Service Bulletins that may apply.
It may be necessary to Test Drive the vehicle again trying different conditions that may cause the DTC to reset.
Were there any problems found or did the DTC reset?
Yes
- Repair as necessary.
- Perform CVT VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - CVT - STANDARD PROCEDURE)
No
- Test Complete.