The driver selects the travel position using the selector lever:

The park/neutral position switch is located on the selector shaft, which is connected to the selector lever by a pull cable. The switch informs the TCM of the current selector lever position.

The selector lever position is transmitted to the TCM in encoded form along 4 lines. The encoding ensures that malfunctions in the connecting lead are identified.

In addition the switch controls the starter interlock, the reversing light and the selector lever position indicator on the instrument panel.

The vehicle A/T OSS is a magnetic inductive pickup that relays information about vehicle speed to the TCM. The TCM uses this information to control the following functions:

The OSS mounts in the case at the speed sensor rotor, which is pressed onto the spur gear. An air gap of 0.1-1.3 mm (0.004-0.050 in) is maintained between the sensor and the teeth on the spur gear. The sensor consists of a permanent magnet surrounded by a coil of wire. As the differential rotates, the OSS generates an AC signal.

The A/T ISS is a magnetic inductive pickup that relays information about the transaxle input speed to the TCM. The TCM uses this information to perform the following functions:

The ISS mounts onto piston B the valve body. An air gap of 1.8-2.2 mm (0.070-0.086 in) is maintained between the sensor and piston B. The sensor consists of a permanent magnet surrounded by a coil of wire. As piston B is driven by the turbine shaft, the ISS induces an AC signal.

Higher vehicle speeds induce a higher frequency and a higher voltage measurement at the sensor. Sensor resistance should measure between 825-835ohms at 20°C (68°F). The sensor can measure between 1,000-8,000 Hz.

The shift solenoids are two identical, normally open, electronic exhaust valves that control upshifts and downshifts in all forward gear ranges. These shift solenoid valves work together in a combination of ON and OFF sequences to control the line pressure and shift mechanisms.

Solenoid 1 controls the flow to each clutch valve by the operation type, that is, if solenoid 1 is ON, line pressure will be low: 87-116 psi (599-799 kPa) (6-8 bar). If solenoid 1 is OFF, line pressure will be high: 232-261 psi (1599-1799 kPa) (16-18 bar). The resistance is assumed to be 26-27ohms.

Solenoid 2 controls the oil flow to the lock-up clutch valve E by the ON/OFF signal.

The TCM monitors numerous inputs to determine the appropriate solenoid state combinations and the transaxle gear for the vehicle operating conditions.

The pressure control valve is a precision electronic pressure regulator that controls the operation of the clutches, brakes, and the TCC.

The valve reduces the system pressure with which the downstream solenoid valves and the electrical pressure regulating valves are supplied. Smaller solenoid valves can be used as a result. This valve requires a constant input pressure.

The TFT sensor is a positive temperature coefficient thermistor that provides information to the TCM regarding transaxle fluid temperature. The temperature sensor is located in the valve body. Calculated temperature is used to determine the shift time and the shift delay time.

The internal electrical resistance of the sensor varies in relation to the operating temperature of the transaxle fluid, as shown in the following chart:

The TCM measures this voltage as another input to help control line pressure, shift schedules, and TCC apply.

On some applications, when transaxle fluid temperature reaches 140°C (284°F), the TCM modifies the transaxle shift schedules and TCC apply in an attempt to reduce fluid temperature by reducing transaxle heat generation. During this time the TCM applies the TCC at all times in fourth gear. Also the TCM commands the 2-3 and the 3-4 shifts earlier to help reduce fluid heat generation. Refer to Transmission Fluid Temperature Sensor Specifications .

The transaxle electrical connector is a very important part of the transaxle operating system. Any interference with the electrical connection can cause the transaxle to set DTCs or affect proper operation

To remove the connector, squeeze the two tabs toward each other and pull straight up, as shown in the illustration.

The following items can affect the electrical connections:

Remember the following points when working with the transaxle wiring connector assembly:

The TCM is an electronic device which monitors inputs in order to control the following conditions within the control program:

Based on this input information, the TCM controls various transaxle output functions and devices.

When one or more operations as listed below are performed, all learned contents which are stored in the TCM memory should be erased after the opperations.

1. Connect the scan tool.
2. Turn the ignition switch to the On position.

Important: Before pushing the Yes button for the TCM initialization on the scan tool, make sure the condition is as follows:

•	Vehicle is in Park.

•	Engine is at idle.

3. Follow the TCM Learned Initialize procedure on the scan tool.

The DLC is a multiple cavity connector, which provides the means to access serial data from the TCM to aid in powertrain diagnosis. The DLC allows the technician to use a scan tool to monitor various systems and display diagnostic trouble codes. The DLC connector is located with the driver compartment, directly below the steering column.

Notice: Lack of basic knowledge of this powertrain when performing diagnostic procedures could result in incorrect diagnostic performance or damage to powertrain components. Do not attempt to diagnose a powertrain problem without this basic knowledge.

Throttle Position Sensor

Automatic Transaxle Output (Shaft) Speed Sensor

Automatic Transaxle Input (Shaft) Speed Sensor

Provides transaxle input speed data to the TCM for determining shift patterns and TCC apply/release, and gear ratio

Engine Coolant Temperature Sensor

Engine Speed

Stop Lamp Switch

Transaxle Fluid Temperature (TFT) Sensor