The transmission control module (TCM) controls the torque converter clutch (TCC) solenoid valve pulse width modulation (PWM). The solenoid directs the hydraulic fluid for TCC apply and release. When the TCC is applied, the engine is coupled directly to the transmission through the TCC. The TCC slip speed should be near 0.
If the TCM detects high torque converter slip when the TCC is commanded ON, then DTC P0741 sets. DTC P0741 is a type B DTC.
This diagnostic procedure supports the following DTC:
DTC P0741 Torque Converter Clutch (TCC) System - Stuck Off
• | No TP sensor DTC P0120. |
• | No ISS DTCs P0716 or P0717. |
• | No OSS DTCs P0722 or P0723. |
• | No TCC performance DTC P0742. |
• | No engine torque signal circuit DTC P2637. |
• | No IMS DTCs P1815, P1820, P1822, P1823, P1825 or P1826. |
• | No TCC solenoid electrical DTCs P2763 or P2764. |
• | The engine run time is greater than 5 seconds. |
• | The IMS range is D2, D3, D4, or D5. |
• | The elapsed time since the most recent range change is greater than 6 seconds. |
• | The transmission fluid temperature is 20-130°C (68-266°F). |
• | The engine torque is greater than 55 N·m (41 lb ft). |
• | The throttle position is 12-90 percent. |
• | The gear ratio is within the following ranges: |
- | 1.56:1 to 1.64:1 - 3rd gear |
- | 0.98:1 to 1.03:1 - 4th gear |
- | 0.73:1 to 0.77:1 - 5th gear |
• | The TCC apply pressure is greater than 200 kPa (29 psi) for more than 2 seconds. |
• | The TCC duty cycle is greater than 80 percent for more than 2 seconds. |
The TCM commands the TCC ON, and the TCC slip is between 150-250 RPM for greater than 8 seconds.
• | The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) during the second consecutive drive trip in which the Conditions for Setting the DTC are met. |
• | The TCM inhibits TCC. |
• | The TCM inhibits 5th gear if the transmission is in Hot Mode. |
• | The TCM freezes transmission adaptive functions. |
• | At the time of the first failure, the TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record. |
• | At the time of the second failure, the ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as a Freeze Frame. |
• | The TCM stores DTC P0741 in TCM history. |
• | The ECM turns OFF the MIL after the sixth consecutive drive trip in which the TCM does not send a MIL illumination request. |
• | A scan tool can clear the DTC. |
• | The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non emission related diagnostic fault occurring. |
• | The TCM cancels the DTC default actions when the ignition is OFF long enough in order to power down the TCM. |
Inspect the transmission fluid lines to the radiator. The lines may be pinched, plugged or twisted.
The numbers below refer to the step numbers on the diagnostic table.
This step inspects the transmission fluid to ensure that it is at the proper level.
This step verifies that the TCC engages when commanded ON by the scan tool.
Step | Action | Value(s) | Yes | No | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||||||||||||
Perform the Transmission Fluid Checking Procedure. Refer to Transmission Fluid Check . Did you perform the Transmission Fluid Checking Procedure? | -- | Go to Step 3 | Go to Transmission Fluid Check | |||||||||||||||||
Important:
Is the slip speed within the specified range? | -20 to +75 RPM | Go to Intermittent Conditions in Engine Controls - 4.6L | Go to Step 4 | |||||||||||||||||
4 |
Did you find and correct any of the above conditions? | -- | Go to Step 5 | -- | ||||||||||||||||
5 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 6 | Go to Step 2 | ||||||||||||||||
6 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK |