Lock-up solenoid, SL
Lock-up solenoid SL is positioned in the valve housing, which is mounted behind the side cover on the transmission. The lock-up solenoid consists of an electrical coil which controls a hydraulic valve. The solenoid is controlled by pulse width modulation (PWM) voltage and is grounded at the ground terminal. The solenoid controls lock-up engagement of the torque converter. Engagement occurs through solenoid pulsing which provides a smooth lock-up engagement function. Power transmission then changes to mechanical power transmission through the torque converter. The hydraulic function of the solenoid is linear.
There is a diagnostic for the electrical function of the solenoid, but not for the hydraulic function.