4T80-E Automatic Transaxle
DTC P0741
Circuit Description
The transmission control module (TCM) controls the torque converter clutch (TCC) solenoid valve pulse width modulation (PWM). The solenoid controls 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.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0741 Torque Converter Clutch (TCC) System - Stuck Off
Conditions for Running the DTC
* No MAF DTCs P0101, P0102 or P0103.
* No MAP DTCs P0106, P0107 or P0108.
* No TP DTCs P0121, P0122 or P0123.
* No OSS DTCs P0722 or P0723.
* No AT ISS DTCs P0716 or P0717.
* No TCC stuck ON DTC P0742.
* The engine run time is greater than 5 seconds.
* The commanded gear is greater than 2.
* The transmission fluid temperature is 20-133°C (68-271°F).
* The TP angle is 2-90 percent.
* The TCC PWM solenoid valve is commanded ON.
* The TCC duty cycle is 65 percent or greater for 2 seconds.
Conditions for Setting the DTC
TCC slip speed is 125 RPM or greater for 8 seconds 2 times during the same ignition cycle.
Refer to Torque Converter Clutch Slip Speed.
Action Taken When the DTC Sets
* The TCM requests the engine control module (ECM) to illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
* The TCM commands maximum line pressure.
* The TCM inhibits TCC.
* The TCM inhibits 4th gear if the transmission is in hot mode.
* The TCM freezes transmission adaptive functions.
* The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records and the TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records.
* The TCM stores DTC P0741 in TCM history during the second consecutive trip in which the Conditions for Setting the DTC are met.
Conditions for Clearing the MIL/DTC
* The ECM turns OFF the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
* The TCM clears the DIC message when the condition no longer exists.
* A scan tool can clear the MIL/DTC.
* The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
* The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM.
Diagnostic Aids
* Inspect the transmission fluid level.
* The transmission may be in hot mode. Inspect the transmission fluid lines to the radiator. The lines may be pinched, plugged or twisted.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
2. This step inspects the transmission fluid to ensure that it is at the proper level.
3. This step verifies that the TCC engages when commanded ON by the scan tool.
