Circuit Description
The Powertrain Control Module (PCM) controls the Torque Converter Clutch Solenoid Valve (TCC Sol. Valve) pulse width modulation (PWM). The solenoid controls the hydraulic fluid for TCC apply and release. When the vehicle is accelerating, the PCM commands the TCC to be disengaged.
When the PCM detects a TCC slip from -5 to +80 RPM when the TCC is commanded OFF, then DTC P0742 sets. DTC P0742 is a Type B DTC.
Conditions for Setting the DTC
| • | No MAF DTCs P0101, P0102 or P0103. |
| • | No TP DTCs P0121, P0122 or P0123. |
| • | No VSS DTCs P0502 or P0503. |
| • | No A/T ISS DTCs P0716 or P0717. |
| • | No TCC Stuck OFF DTC P0741. |
| • | No TFP Val. Position Sw. DTC P1810. |
| • | No TCC PWM Sol. Valve DTC P1860. |
| • | The engine run time is greater than 5 seconds. |
| • | The engine is not in fuel cut off. |
| • | The TFP Val. Position Sw. indicates D4. |
| • | The transmission gear ratio indicates 2nd, 3rd or 4th gear. |
| • | The throttle angle is greater than 11.8°. |
| • | The delivered torque is 135-270 N·m (100-200 lb ft). |
| • | The PCM commands the TCC Sol. Valve OFF. |
Fault Criteria: The slip speed is -5 to +80 RPM for 6 seconds (Slip speed equals engine speed minus transmission input shaft speed).
Action Taken When the DTC Sets
| • | The PCM illuminates the Malfunction Indicator Lamp (MIL). |
| • | SERVICE ENGINE SOON displays on the Driver Information Center (DIC). |
| • | The PCM inhibits TCC engagement. |
| • | The PCM inhibits 4th gear if the transmission is in hot mode. |
| • | DTC P0742 is stored in the PCM history. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL after three consecutive trips without a failure reported. |
| • | A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported. |
| • | The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the PCM. |
Diagnostic Aids
Inspect the transmission fluid for sediment or debris.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step verified that the PCM commanded the TCC Sol. Valve OFF and the slip speed is -5 to +80 RPM for more than 6 seconds.
-
This step inspects and repairs the components that caused the DTC to set.
Step | Action | Value(s) | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to A Powertrain On Board Diagnostic (OBD) System Check | |||||
Important: Before clearing the DTC(s), use the scan tool in order to record the Freeze Frame and Failure Records for reference. Using the Clear Info function will erase the stored Freeze Frame and Failure Records from the PCM. Did DTC P0742 set within 6 seconds? | -- | Go to Diagnostic Aids | ||||||
Inspect and repair the following items:
Refer to unit repair. Is the inspection and repair complete? | -- | -- | ||||||
4 | In order to verify your repair, perform the following procedure:
Has the test run and passed? | -- | System OK |
