Torque Converter Clutch Solenoid Valve Control

The torque converter clutch solenoid valve is controlled by the TCM. The plunger closes the drain circuit during the OFF period, and opens the circuit during the ON period. If the percentage of OFF-time increases in one cycle, the pilot pressure drain time is reduced and pilot pressure remains high.

The torque converter clutch piston is designed to slip to adjust the ratio of ON-OFF, thereby reducing lock-up shock.

Fig 1: Identifying Torque Converter Clutch Solenoid Valve Control

Courtesy of NISSAN MOTOR CO., U.S.A.

OFF-time INCREASING

darr

Amount of drain DECREASING

darr

Pilot pressure HIGH

darr

Lock-up RELEASING

Fig 2: Identifying Pilot Pressure Solenoid Valve Off-Time Ratio Graph

Courtesy of NISSAN MOTOR CO., U.S.A.