P0740 Torque Converter Clutch, No RPM Drop at Lockup

SYMPTOM
P-0740 TORQUE CONV CLUTCH, NO RPM DROP AT LOCKUP

WHEN MONITORED
Continuously when no matured or maturing Trouble Code and throttle position >10% and constant for 4.4 seconds before TCC engagement requested: No TCC solenoid circuit, any cam/crank-related code, VSS, any TPS-related code and Battery voltage >11.0

SET CONDITION
Torque Converter malfunctions that are detected are the FTC not locking up properly when desired, and the torque converter not unlocking properly when desired. 3 consecutive test failures over one trip will store the code. 2 bad trips will set the code.

POSSIBLE CAUSES
- Fused ignition switch output circuit open
- Diff, shaft, or gears defective
- TCC solenoid defective
- Torque converter assembly defective or TCC solenoid stuck
- Transmission fluid dirty or level low
- Vehicle configuration non-standard