Built Before 6/17/96

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION
The Torque Converter Clutch Solenoid Valve (TCC Sol Valve) acts on the hydraulic fluid, controlling TCC apply and release. The TCC used is the Electronically Controlled Convener Clutch (EC3, pronounced E-C cubed). The EC3 allows the TCC to slip without excessive wear. This allows smooth application and release of the TCC. The PCM will normally allow a small amount of slip to occur with the EC3. This limits the fluid pressure in the torque converter. Very high pressure in the torque converter will damage the converter. When the TCC PWM Sol. Valve engages the TCC, TCC slip speed is approximately 20 RPM. If the PCM detects 3 occurrences of TCC slip of -20 to +25 RPM when the TCC is commanded OFF, then DTC P0742 sets. DTC P0742 is a type B DTC.

CONDITIONS FOR SETTING THE DTC

^ No Throttle Position (TP) DTCs P0122 or P0123.
^ No Vehicle Speed Sensor (VSS) DTCs P0502 or P0503.
^ No TCC PWM solenoid electrical DTC P1860.
^ No TCC enable solenoid electrical DTC P0740.
^ The engine has been running for 8 seconds.
^ Not in fuel shut off.
^ The engine speed is 80-4000 RPM.
^ The PCM has commanded the TCC OFF.
^ The commanded gear is not 1st.
^ No gear range change for greater than 3 seconds.
^ The transmission gear range is D4, D3, or D2.
^ The throttle angle is 14-50%.
^ The engine torque is 95-270 Nm (70-200 ft lbs.).
^ The vehicle speed is 32-112 km/h (20-70 mph).
^ The TCC slip speed is -20 to +25 RPM, 3 occurrences for 8 seconds.

ACTION TAKEN WHEN THE DTC SETS
The PCM illuminates the Malfunction Indicator Lamp (MIL) after two consecutive trips with a failure reported.

CONDITIONS FOR CLEARING THE DTC

^ The PCM turns OFF the MIL after three consecutive ignition cycles 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.

DIAGNOSTIC AIDS

^ Check for PRNDL DTC P0705. DTC P0705 affects transmission operation. This may set DTC P0742 falsely.
^ Inspect the transmission fluid for debris.

TEST DESCRIPTION
The step number below refers to the step numbers on the diagnostic table.

2. A TCC slip speed of -20 to +25 RPM indicates that this DTC is not current. Refer to the Diagnostic Aids. Inspect for PRNDL DTC P0705.