#
TORQUE CONVERTER CLUTCH (TCC) OPERATION

BHE051318901T17

## TCC release

• The TCM stops driving the TCC solenoid (OFF) when TCC release is determined.

## TCC engagement

• When the TCM determines TCC engagement, the TCM gradually increases the duty ratio energizing the TCC solenoid, and gradually drains the oil pressure in the torque converter F chamber.

• The TCC piston slowly presses against the converter cover, and the TCC engages smoothly.

1 | Torque converter F chamber
2 | Torque converter pressure
3 | Torque converter pressure (drain)
4 | Oil cooler
5 | TCC solenoid
6 | Pilot pressure
7 | TCC control valve

## Determination of TCC inhibition

• The TCC is inhibited when any of the following conditions are met.

  – ATF temperature is low.
  – Throttle valve is closed.
  – Failure is detected by diagnosis function.