Torque Converter Clutch Solenoid Valve Control

WARNING: This page is about a different car, the 2003 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

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.

Fig 1: Torque Converter Clutch Solenoid Valve Control Diagram

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

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

Fig 2: Torque Converter Clutch Solenoid Valve Control Flow Chart

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

Fig 3: Pilot Pressure VS Torque Converter Clutch Solenoid Valve Off Time Ratio Graph

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