P0740 OBD Trouble Code

Torque Converter Clutch Circuit/Open

Torque Converter Clutch Circuit Conditions

No PCM or TCM codes set, vehicle in 3rd gear with TCC unlocked for 10 seconds, VSS less than 70 mph, throttle applied to 1/3 open until the TCC locks, TCC locked for 5 seconds, then test started and the PCM detected that the engine speed (RPM) did not drop with the TCC engaged

TCC Enable Circuit Electrical (4L60-E Transmission)

Engine speed over 450 rpm for 5 seconds, system voltage from 10-18v, Fuel Cutoff not active, then the VCM detected one of the following conditions for 5 seconds Condition 1: TCC solenoid commanded on and voltage feedback remained high Condition 2: TCC solenoid commanded off and voltage feedback remained low

Torque converter clutch solenoid - voltage low

Wiring, clutch solenoid, TCM