Transmission Control Systems: Description and Operation

The Mitsubishi F4A22 F4A23, and W4A32 are fully automatic four-speed electronically controlled transaxles. These transaxles are used on all Colt Vista and Eagle Summit Wagon models. The W4A32 transaxle incorporates a transfer case assembly for All Wheel Drive. All models are equipped with a lock up torque converter.

The Electronic Control Unit receives inputs from the following:

- Pulse Generator "A"
- Pulse Generator "B"
- Coolant Temperature Sensor
- Oil Temperature Sensor
- Throttle Position Sensor
- Idle Motor Position Switch
- Accelerator Switch
- Inhibitor Switch
- Kickdown Servo Switch

The Electronic Control Unit calculates if a shift change is needed and controls the following outputs:

- Damper Clutch Control Solenoid Valve
- Pressure Control Solenoid Valve
- Shift-Control Solenoid Valves