Celica GT Convertible L4-2164cc 2.2L DOHC MFI (1997)
Shift Solenoid: Description and Operation
Shift Solenoid "E" (SL)
SYSTEM DESCRIPTION
The ECM uses the signals from the throttle position sensor and air-flow meter to monitor the engagement condition of the lockup clutch.
Then the ECM compares the engagement condition of the lockup clutch with the lock-up schedule in the ECM memory to detect mechanical
trouble of the shift solenoid valve SL, valve body and torque converter clutch
CIRCUIT DESCRIPTION
The shift solenoid valve SL is turned ON and OFF by signals from the ECM to control the hydraulic pressure acting on the lock-up relay valve,
which then controls operation of the lock-up clutch.
Fail safe Function
If the ECM detects a malfunction, it turns the shift solenoid valve SL OFF.