Shift Control

The shift is regulated entirely by electronic control to accommodate vehicle speed and varying engine operations. This is accomplished by electrical signals transmitted by the revolution sensor and throttle position sensor. This results in improved acceleration performance and fuel economy.

Control of Shift Solenoid Valves A and B 

The TCM activates shift solenoid valves A and B according to signals from the accelerator pedal position sensor (throttle position sensor) and revolution sensor to select the optimum gear position on the basis of the shift schedule memorized in the TCM.

The shift solenoid valve performs simple ON-OFF operation. When set to ON, the drain circuit closes and pilot pressure is applied to the shift valve.

Fig 1: Shift Solenoid Valve Performs Simple On-Off Operation Chart

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

Relation between shift solenoid valves A and B and gear positions 

Fig 2: Shift Solenoid Valves A And B And Gear Positions Chart

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

Control of Shift Valves A and B 

Fig 3: Identifying Shift Control Valves A And B Pilot Pressure

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

Pilot pressure generated by the operation of shift solenoid valves A and B is applied to the end face of shift valves A and B.

The drawing above shows the operation of shift valve B. When the shift solenoid valve is ON, pilot pressure applied to the end face of the shift valve overcomes spring force, moving the valve upward.