Diagnosis - A-340E: Description: Introduction

Automatic transmission for all models and configurations is electronically controlled.

The transmission shifting and torque converter lock-up are controlled by electric solenoids mounted to valve body. Solenoids are operated by the Electronic Controlled Transmission (ECT) Electronic Control Unit (ECU). The transmission valve body is equipped with a additional solenoid that affects shift feel by controlling accumulator pressure.

NOTE: The Electronic Controlled Transmission (ECT) Electronic Control Unit (ECU) is used for controlling the engine fuel injection system and transmission. On all models, control unit is referred to as the ECT ECU.

An Overdrive (OD) switch is mounted on shift lever. See Figure and Figure. When OD switch is depressed to ON position, transmission will shift into 4th gear when shift lever is in "D" position, and OD OFF light on instrument panel will go off. When OD switch is released to OFF position, transmission will shift into 3rd gear, and OD OFF light on instrument panel will come on. The OD OFF light is located on instrument panel.

A pattern select switch is located on instrument panel or near shift lever. See Figure and Figure. Pattern select switch has a POWER (depressed) and a NORMAL (released) operating position. When pattern select switch is depressed, transmission upshifts and downshifts will occur at a higher vehicle speed than with switch released. An indicator light on instrument panel indicates when pattern select switch is in POWER position.

Transmission is equipped with shift and key lock system. Shift lock system prevents shift lever from being moved from Park unless brake pedal is pressed. In case of malfunction, shift lever can be released by pressing shift lock override button, located near shift lever. Key lock system prevents ignition key from being moved from ACC to LOCK position unless shift lever is in Park position.