P0740 Torque Converter Clutch, No RPM Drop at Lockup

SYMPTOM
P-0740 TORQ CON CLU, NO RPM DROP AT LOCKUP

WHEN MONITORED
Run in thirdw/ converter unlocked for 10 sec, apply throttle until it locks then run for 5 sec. No TC's for TCC sole., Any cam/crank cond., VSS, TPS signal, TPS voltage high, TPS voltage low.

SET CONDITION
Torque converter malfunctions are detected when it does not lock up or unlock properly. Two consecutive trips that fail will store codes. Mountainous terrain will cause this trouble code.

POSSIBLE CAUSES
- Fused ignition switch output circuit open
- TCC operation okay at this time
- TCC sol defective
- Torque converter assembly def or TCC sol stuck
- Transmission fluid dirty or level low
- Vehicle configuration non-standard