General Description

DESCRIPTION
The 4F2OE electronically controlled automatic transaxle features a combination of electronic and mechanical systems to control forward gear shifting, torque converter lockup for quietness and economy, and a self-diagnosis capability for simplifying troubleshooting procedures.

OPERATION
A Power E-AT switch allows two shift schedules to be selected to tailor transaxle operation to specific driving conditions. The normal (Power E-AT switch released) provides increased fuel economy by providing earlier partial throttle upshifts. The power mode (Power E-AT switch depressed) provides delayed upshifts at part throttle utilizing more engine power. The Transaxle Control Module (TCM) has the capability to override the power mode depending on driving conditions.






Electronic Control System
The electronic system controls the transaxle shifting in forward speeds and torque converter lockup by means of solenoid actuated valves. These solenoid valves, when energized, actuate friction elements (clutches and band) to control shifting in the planetary gear. The shift timing and lockup events are regulated by the Transaxle Control Module (TCM) in programmed logic and in response to input sensors and switches to produce optimum driveability.

Overdrive Control
The transaxle control system is equipped with an Overdrive On/Off button used to inhibit fourth gear operation. The O/D OFF lamp on the instrument panel will illuminate when fourth gear has been "locked out". If the Overdrive On/Off button is depressed during fourth gear operation, a 4-3 downshift will occur. The Overdrive On/Off button should be used when descending hills or during city driving to increase engine braking. The Overdrive On/Off switch is located on the end of the selector lever.