Automatic Transmission System (For 3Ur-Fe) - System Description

The Electronic Controlled Automatic Transmission (ECT) is an automatic transmission that electronically controls shift timing using the Engine Control Module (ECM). The ECM detects electrical signals that indicate engine and driving conditions, and controls the shift point based on driver habits and road conditions. As a result, fuel efficiency and power transmission performance are improved.


Shift shock is reduced by controlling the engine and transmission simultaneously.

Automatic Transmission System (For 1Ur-Fe) - L4 Position Switch Circuit

The four wheel drive control ECU judges whether the transfer is in the L4 position based on the information from the limit switch inside the transfer shift actuator assembly which is detected by the ECM. The four wheel drive control ECU then inputs a signal to the combination meter assembly via CAN communication and turns on the 4LO indicator.

Automatic Transmission System (For 1Ur-Fe) - Pattern Select Switch 2Nd Start Mode Circuit

When 2nd mode is selected with the pattern select (2ND) switch, the ECM controls the solenoid valves and the transmission starts from 2nd gear.


The 2nd mode is the system that operates the throttle motor to control engine output to reduce skidding of the driving wheels, and guarantee takeoff acceleration, driving straightness and turning stability.


When the shift lever is in D, the transmission automatically shifts up through 3rd to 6th as usual.

Automatic Transmission System (For 1Ur-Fe) - Pattern Select Switch Power Mode Circuit

The ECM memory contains the programs for the normal and power shift patterns and lock-up pattern.


By following the programs corresponding to the signals from the pattern select switch, the park/neutral position switch and other various sensors, the ECM switches the solenoid valves on and off, and controls the transmission gear change and the lock-up clutch operation.

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