Sidekick 2WD L4-1590cc 1.6L SOHC 0 TBI 8V (1992)
Torque Converter Clutch Relay: Description and Operation
Lock-Up Relay Circuit
This system control lock-up of the A/T torque convertor.
The lock-up solenoid, under control from the stop light switch, A/T oil pressure switch and lock-up relay, opens and closes the oil passage to lock and
unlock the torque convertor.
Lock-Up Relay ON Zone
The factors which the ECM uses to control the lock-up relay are the signals from the throttle position sensor (throttle plate angle), ignitor (engine rpm)
and engine coolant temperature. It energizes the solenoid only during a certain throttle valve opening angle (shaded area in illustration) and only when
the engine temperature is 60° C (140° F) or higher.
Battery voltage is supplied to the solenoid only when the relay is energized, the brake pedal is released and the A/T oil pressure is higher than a specific
point (A/T pressure switch is ON).
Even when the lock-up relay is ON, if the brake pedal is pressed or the A/T oil pressure is low, the lock-up circuit opens and no voltage is applied.
