4T45-E Automatic Transaxle
DTC P0741 (3.5L)
Circuit Description
The torque converter clutch (TCC) solenoid valve is a pulse width modulation (PWM) solenoid. When vehicle operating conditions are appropriate for TCC application, the powertrain control module (PCM) begins the TCC duty cycle at approximately 42 percent. The PCM then increases the duty cycle up to 90 percent, in order to achieve full TCC apply pressure.
When the TCC PWM solenoid valve is de-energized, the solenoid blocks filtered 2-3 drive fluid, and allows TCC signal fluid to exhaust. When energized, the solenoid modulates fluid into the TCC signal fluid circuit. When fully energized, modulation stops, and the solenoid blocks both 2-3 drive fluid and TCC signal fluid exhaust.
When the PCM detects a high TCC slip speed 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 P0107 or P0108.
^ No TP DTCs P0120 or P0220.
^ No VSS DTCs P0502 or P0503.
^ No ISS DTCs P0716 or P0717.
^ No TCC stuck ON DTC P0742.
^ No TCC release switch DTC P1887.
^ No TCC electrical DTCs P2761.
^ The engine is running for 5 seconds or more and not in fuel cut off.
^ The transmission fluid temperature is between 20°C (68°F) and 130°C (266°F).
^ The commanded gear is 3rd or 4th.
^ The TP indicated angle is 5 percent or more.
^ The PCM commands TCC duty cycle 60% or greater for 3 seconds or more.
^ The engine torque is greater than 76 Nm (56 ft. lbs.)
Conditions for Setting the DTC
The TCC slip speed is greater than 200 RPM for 6 seconds.
Action Taken When the DTC Sets
^ The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
^ The PCM forces the TCC OFF.
^ The PCM inhibits TCC engagement.
^ The PCM freezes transmission adaptive functions.
^ The PCM inhibits 4th gear when in HOT mode.
^ The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
^ The PCM stores DTC P0741 in PCM history during the second consecutive trip in which the Conditions for Setting the DTC are met.
Conditions for Clearing the MIL/DTC
^ The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
^ A scan tool can clear the MIL/DTC.
^ The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
^ The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM.
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.
