Torque Converter Clutch Solenoid

Torque Converter Clutch Solenoid Description

The TCM energises the lock-up solenoid valve to engage the lock-up clutch. Lock-up clutch operation is dependent on throttle position, engine speed, operating mode and the range selected on the transfer box. Unique lock-up maps, similar to the shift maps, are incorporated in the economy and sport modes for all forward gears. Engagement and disengagement of the lock-up clutch is dependent on throttle position and engine speed.

There are four TCC solenoid diagnostics, an error is detected if:
1. The ignition supply is greater than 9V and the solenoid voltage is greater than 2.5V with the driver OFF.
This indicates a short circuit to battery positive.
2. The ignition supply is greater than 9V and the solenoid voltage is less than 3.5V with the driver ON.
This indicates an open circuit or a short circuit to ground.
3. Warm up is complete, the transfer box is in high range, engine torque is greater than 100 Nm, the TCC is closed and the TCC performance is out of range.
4. The ignition supply is greater than 9V, there is no gear ratio fault and the TCC performance is out of range.

For the diagnostic table, please refer to the individual codes (i.e. P0722, P0741 or P0743).

If the above table does not include details of the following enabling conditions: - AT, ECT, vehicle speed range, and time after engine start-up then the state of these parameters has no influence upon the execution of the monitor.