The design of the transmission of models of later years of production (since 1992) with engines 4.2 l EFI differs only in minor modification of some internal components and large dimensions of the rotation converter.
The choice of overdrive on models of later years of production is carried out using a push button mounted in the selector lever handle. When the button is depressed, the transmission is shifted to overdrive fourth gear with increasing speed. When the button is released, fourth gear is disabled. This mode is useful when engine braking is required, or to prevent frequent shifting from third to fourth gear, such as when driving in a busy city cycle.
The electronic control system consists of an electronic control unit (ECU), operating in conjunction with the throttle position sensor (TPS), throttle switch, engine speed sensor, rpm sensor, vehicle speed sensor, transmission oil temperature sensor, power mode switch, kickdown switch and start enable switch.
If any of the sensors / sensors-switches fail, the ECU switches on the emergency mode of the AT operation, in which the car can be driven to the nearest workshop of the manufacturer's dealership for professional repairs. At low AT temperatures, the transmission oil temperature sensor does not allow upshifting and blocking the rotation converter.
The power selector controls the order in which the transmission shifts. When the switch is in the AUTO position, the transmission shifts to fourth gear as the vehicle speed increases, thereby reducing fuel consumption. However, when accelerating hard, the Power Shift Warning Light may come on, indicating that the transmission shift mode has been changed to improve the efficiency of the engine output. When the switch is in the POWER position, the transmission does not shift into fourth gear, maximizing engine braking performance, such as when descending a steep descent.
The mode switch on late models is located in the central part of the instrument panel and allows you to switch between three modes: AUTO, POWER and HOLD. The POWER mode is used when accelerating hard or during a steep climb. The AUTO position corresponds to normal fuel economy mode. Setting the HOLD mode allows you to hold the transmission in the gear selected by the selector lever (I, II, III or OVERDRIVE (raising)).
Hydraulic transmission fluid circulates through an oil cooler located in the radiator. The oil cooler is connected to the transmission through pipes. The transmission fluid level is monitored using a dipstick located on the right side of the engine compartment.
The transmission is removed from the vehicle assembly after the preliminary removal of the transfer case.
Note. Since detailed diagnostics and overhaul of AT require highly qualified personnel and special equipment, the compilers of this Guide recommend that if problems arise, in addition to those listed in the Section on troubleshooting vehicle, contact the workshop of the dealership of the manufacturer.
Procedures for removing and installing the transmission assembly (e.g. for delivery to a workshop for repair or replacement) described in this chapter.