Description & Operation: Introduction
The A-541E automatic transaxle is electronically controlled. Transaxle shifting and Torque Converter Clutch (TCC) lock-up are controlled by an Engine Control Module (ECM). ECM receives information from various input devices and uses this information to control the shift solenoids No. 1 and No. 2 for transaxle shifting, SLN solenoid to control transaxle line pressure, and SL solenoid for TCC lock-up. All solenoids are located on the valve body. See Fig 1.
An Overdrive (O/D) switch is mounted on gearshift lever. See Fig 1. When O/D main switch is depressed to ON position and gearshift lever is in "D" position, transaxle will shift into 4th gear and O/D OFF indicator on instrument panel will go off. When O/D main switch is released to OFF position, transaxle will shift into 3rd gear and O/D OFF indicator will illuminate.
Transaxle is equipped with a shift lock and key lock system. Shift lock system prevents gearshift lever movement from Park unless brake pedal is applied. In case of a malfunction, gearshift lever can be released by depressing shift lock override button located near gearshift lever. Key lock system prevents ignition switch movement from ACC to LOCK position unless gearshift lever is in Park. For more information on shift lock and key lock system, see SHIFT INTERLOCK SYSTEMS - LEXUS & TOYOTA article.