Torque Converter Lock-Up System: Notes

The lock-up mechanism of the TCC operates in the D position in 2nd, 3rd, 4th, and 5th gears, in the I position in 2nd and 3rd gears, and in the L position in 2nd gear. The pressurized fluid is drained from the back of the torque converter through a fluid passage, causing the TCC piston (2) to be held against the torque converter cover (1).

As this takes place, the mainshaft (3) rotates at the same speed as the engine crankshaft. Together with the hydraulic control, the PCM optimizes the timing and amount of the lock-up mechanism. When the TCC solenoid valve is turned on by the PCM, the TCC solenoid valve pressure switches the lock-up shift valve lock-up on and off. The AT CPC solenoid valve C and the lock-up control valve control the amount of lock-up.