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The mechanical components are as follows:
| • | Torque Converter |
| • | Trochoid-type Oil Pump Assembly |
| • | Planetary Gear Unit--Planetary gear unit shifts the gear position to forward, reverse, or neutral while driving. The unit consists of a sun gear, a planetary carrier, and an internal gear. The different engagement patterns of this unit installed in the front and rear operate when driving forward, backward, and shifting. |
| • | Clutches and Brakes--To shift gears via the planetary gear unit, clutches and brakes are used to engage and lock the components of the front and the rear. Clutches and brakes, except the one-way clutch, are operated by oil pressure switched by the valve body, the shift valve, and the solenoid valve. |
| • | Low Clutch Assembly--The low clutch causes an engagement between the rear internal gear and the front planetary carrier. |
| • | Low and Reverse Brake Assembly--The low and reverse brake locks the front planetary carrier in reverse gear in the "R" range when the vehicle is moving backward. In other cases, the brake operates in 1st gear in the 1 range with the low clutch because of locking the rear internal gear. It operates to obtain engine brake in the 1 range. |
| • | High Clutch Assembly--The high clutch causes an engagement between the front planetary carrier and the input shaft. It operates in 3rd and 4th gears. |
| • | Reverse Clutch Assembly--The reverse clutch causes an engagement between the front sun gear and the input shaft. It operates with the low and reverse brake when the vehicle is moving backward. |
| • | Low One-Way Clutch Assembly--The low one-way clutch prevents reverse rotation of the front carrier and the rear internal gear with low clutch. It operates mechanically without being operated by oil pressure. |
| When the front carrier and the rear internal gear with low clutch rotate clockwise, even if engine braking is desirable, engine braking does not occur. |
| • | 2-4 Brake and Brake Servo Assembly--The 2-4 brake and brake servo lock the front sun gear. They operate in 2nd and 4th gears. Operation is via the 2-4 brake servo. Line pressure is applied to the engagement and release sides. The brake operates when line pressure is applied to the engagement side only. The 2-4 brake does not operate when line pressure is applied to both the engagement and release sides. |
| • | Lock-up Clutch--The lock-up clutch is employed inside the torque converter to lock up when creation conditions are met in 3rd and 4th gears. |
| • | Control Valve Body Assembly--The valve body delivers oil pump discharge pressure to the clutches and brakes. |
| The valve body consists of a manual valve which delivers basic oil pressure, shift valves which switch the oil pressure circuit to the clutches and brakes, a pressure regulator valve which regulates line pressure, and accumulators which practise smooth shift shock. |
| In the valve body, there are oil circuits. Shift valves are operated by the shift solenoid valves. |
| • | Valves and Solenoids |
| — | Pressure Regulator Valve: The pressure regulator valve regulates the oil pump discharge pressure to the set pressure. ATF for which oil pressure has been regulated lubricates the rotating parts, the torque converter and the inside of the valve. The oil pressure changes in response to the driving range and throttle position. |
| — | Manual Valve: The manual valve delivers the line pressure directly via the select lever. |
| — | Pilot Valve: The pilot valve holds the oil pressure steady which fluctuates according to driving conditions. The oil pressure which has passed through this valve is called the pilot pressure. It is delivered through each of the solenoid valves to the operation side of the shift valves and the pressure modifier valve. |
| — | Pressure Modifier Valve: The pressure modifier valve is operated via pilot pressure which is itself regulated by the pressure control solenoid valve. The oil pressure which has passed through this valve is called the modifier pressure. The modifier pressure operates the pressure regulator valve and the accumulator control valve. Thus, the line pressure changes in response to driving conditions. |
| — | Shift Valve A: Shift valve A switches the line pressure applied to shift valve B and the line pressure applied to the engagement side of the 2-4 brake servo. This valve is operated by switching the pilot pressure. Switching the pilot pressure is controlled by shift solenoid valve A. |
| — | Shift Valve B: Shift valve B switches the line pressure applied to each clutch and brake, and the pilot pressure applied to the neutral shift valve and the lock-up control valve. This valve is operated by switching the pilot pressure. |
| Switching the pilot pressure is controlled by the shift solenoid valve B. |
| — | 1-2 Shift Solenoid Valve (Shift Solenoid A): 1-2 shift solenoid valve controls the pilot pressure which operates shift valve A. ON opens the valve for the pilot pressure; OFF closes it. |
| — | 2-3 Shift Solenoid Valve (Shift Solenoid B): 2-3 shift solenoid valve controls the pilot pressure which operates shift valve B. ON opens the valve for the pilot pressure; OFF closes it. |
| — | Servo Release Timing Valve: The servo release timing valve adjusts the timing for applying the line pressure to the release side of the 2-4 brake servo to the same as that of the timing for applying the line pressure to the low clutch and the high clutch when shifting from 2nd gear to 3rd or from 4th gear to 3rd gear. |
| — | Pressure Control Solenoid Valve: The pressure control solenoid valve regulates the pilot pressure applied to the pressure modifier valve in response to the throttle position. Operation of the valve is duty-controlled. |
| — | Accumulator: This valve prevents an abnormal line pressure rise from being applied to each brake and clutch. The oil pressure rise is controlled by the line pressure (back pressure) applied by the accumulator control valve. |
| — | Accumulator Control Valve: The accumulator control valve regulates the line pressure (back pressure) applied to each accumulator. This valve is operated via the pilot pressure regulated by the pressure modifier valve. |
| — | Torque Converter Clutch (TCC) Solenoid Valve: The TCC solenoid valve regulates the pilot pressure which operates the lock-up control valve during lock-up. Operation of the valve is duty-controlled. |
| — | Lock-up Control Valve: The lock-up control valve controls oil pressure applied to the lock-up clutch in the torque converter by means of pilot pressure regulated by the TCC solenoid. |
| — | Neutral Control Valve: The neutral control valve absorbs fluctuation of line pressure applied to the low clutch. |
| — | Oil Pressure Circuit: To shift gears, two types of oil pressure, line pressure and pilot pressure, are used. |
| Line pressure which operates clutches and brakes is controlled by the manual valve and shift valves A and B. Pilot pressure which is line pressure regulated by the pilot valve operates shift valves A and B and the lock-up control valve. It is controlled by shift solenoid valves A and B and the TCC solenoid. Line pressure is regulated by the pressure regulator valve in response to the pressure modifier valve (throttle position) and the manual valve (selector lever position). |
The electrical components are as follows:
| • | Transmission Control Module (TCM) |
| • | Input and Output Speed Sensor Assembly |
| • | Park/Neutral Position Switch (PNP) |
| • | Transmission Fluid Temperature (TFT) Sensor |
For more information, refer to Electronic Component Description .
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