Description & Operation
This automatic is a full automatic type with 3 speeds plus overdrive. The torque converter is a 3 element, one step and 2 phase type and is equipped with an electronically controlled lock up mechanism. The internal drive components consist of 3 sets of planetary gear units. 3 disc type clutches, 4 disc type brakes and 3 one-way clutches. See Fig 1 .
The AW03-72LE and AW03-73LE 4-speed OD transmissions are electronically controlled. Transmission shifting and torque converter clutch lock-up are controlled by either a Powertrain Control Module (PCM) or a Transmission Control Module (TCM) depending on model, 2 shift solenoids and a lock-up solenoid. For electronic diagnosis, see appropriate ELECTRONIC CONTROLS article.
The control module receives information from various input devices and uses this information to control torque converter lock-up solenoid and shift solenoids No. 1 and 2 on transmission valve body. Solenoids are responsible for transmission shifting and torque converter clutch lock-up. A mode switch is mounted on console and is used to change shift program from ECONOMY to POWER.