Toyota LAND CRUISER, Service Manual Supplement

Page: 79 / 409

AT-9
AUTOMATIC TRANSMISSION (STATION WAGON) - OPERATION
3. ELECTRONIC CONTROL SYSTEM
The electronic control system for the A442F automatic transmission provide extremely precise control
of the gear shift timing and lock-up timing in response to driving conditions as sensed by various sen-
sors located throughout the vehicle and in response to the engine's running condition.
At the same time, the ECT ECU control reduces vehicle squat when the vehicle starts out and gear
shift shock.
The electronic control system for controlling the shift timing and the operation of the lock-up clutch is
composed of the following three parts:
(a) Sensors: These sense the vehicle speed and throttle position and send this data to the ECT ECU in the
form of electronic signals.
(b) ECT ECU: This determines the shift and lock-up timing based upon the signals from the sensors.
(c) Actuators: Solenoid valves divert hydraulic pressure from one circuit of the hydraulic control unit to
another thus controlling shifting and lock-up timing.
1FZ-FE engine only