Diagnostic AIDS

Tech 1 only indicates when PCM has commanded TCC driver on, this does not confirm that TCC is actually engaged. Road test vehicle to determine if TCC is properly functioning. Engine RPM should decrease when Tech 1 indicates TCC has been turned on. If diagnosis indicates all electrical circuits and components are okay, check for hydraulic and mechanical problems.

Fig 1: Code P0740 Schematic (3.8L) Torque Converter Clutch

Fig 2: Code P0740 Flow Chart (3.8L) Torque Converter Clutch

Fig 3: Code P0740 Flow Chart