General Information

Automatic Transaxle
P0744 Torque Converter Clutch Circuit - Open or Short to ground (SOL 6) - General Information

Component Location





General Description

The PCM/TCM controls the locking and unlocking of the Torque Converter Clutch (or Damper Clutch), to the input shaft of the transmission, by applying hydraulic pressure. The main purpose of T/C clutch control is to save fuel by decreasing the hydraulic load inside the T/C. The PCM/TCM outputs duty pulses to control the Damper Clutch Control Solenoid Valve (DCCSV) and hydraulic pressure is applied to the DC according to the DCC duty ratio value. When the duty ratio is high, high pressure is applied and the Damper Clutch is locked.

DTC Description

TCM set this code If detected short to Ground for Torque convertor clutch solenoid. (MIL ON : 2 driving Cycle)

DTC Detecting Condition





CAUTION :
1. The function with the higher priority will always take precedence. However, a low-priority is not overruled by a higher priority function.
2. Functions from different priority categories can also run in parallel. It is important to note which function will take precedence in this case.
3. In such an event it is possible for a substitute function with low priority not be carried out if a second, higher-priority function is present. This has been taken into account when compiling the priority list and is international.
4. The mechanical emergency run function must always have the highest priority, since from the electrical standpoint it is the only safe condition.

Signal Waveform & Data

Solenoid valve operating status according to gear position





-O- : variable control
















Fig 1) Slip lockup status of Torque Converter at D3
Fig 2) Lock up release status when shifting up from 3rd gear to 4th gear
Fig 3) Slip lock up status while driving at 5th gear
Fig 4) Full release status at 6th gear