P0740 Torq Conv Clutch, No RPM Drop at Lockup

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

WHEN MONITORED
Continuously with the key on. Not in Park or Neutral and no other MIL (trouble codes) illuminations.

SET CONDITION
If the TCC cannot achieve the desired drop in engine RPM when the TCC solenoid is near maximum duty cycle. Three consecutive bad tests are required to set the code.

POSSIBLE CAUSES
- "MISFIRE TROUBLE" code set
- Vehicle stalls (torque converter clutch solenoid)
- Torque converter clutch shaft(s)/seal defective
- Transmission fluid contaminated
- No problems diagnosed
- TCC solenoid wiring harness observable def
- Torque converter clutch defective
- Torque converter clutch hydraulic circuit damaged