P0742 CHEVROLET - Torque Converter Clutch Circuit Stuck On
- Dirty transmission fluid
- Faulty torque converter clutch solenoid valve
- Torque converter clutch solenoid valve harness or connectors
- Torque converter clutch solenoid valve circuit is open or shorted
- Transmission internal mechanical problem
There is a factory service bulletin for the following Chevrolet Models:
2001 Chevrolet Lumina
2001-2005 Chevrolet Venture, Venture EXT, Venture 4WD
2001-2007 Chevrolet Monte Carlo
2001-2008 Chevrolet Impala, Lumina (Export Only)
2005-2008 Chevrolet Uplander, Uplander EXT, Uplander 4WD
Chevrolet Factory Service Bulletin P0742 OBDII Code
When the PCM detects low torque converter slip when the PCM commands the TCC OFF, then is sets the P0742 code.
The Torque Converter Clutch (TCC) solenoid valve is a normally-open exhaust valve that is used with the Torque Converter Clutch Pulse Width Modulation (TCC PWM) solenoid valve in order to control fluid acting on the converter clutch apply valve. The TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. When grounded (energized) by the Powertrain Control Module (PCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes converter signal oil pressure to increase and move the converter clutch apply valve against spring force and into the apply position. In this position, release fluid is open to an exhaust port and converter feed fluid fills the apply fluid circuit. The converter feed fluid applies the TCC.