Part 1

TRANSAXLE OPERATION

Transaxle Operation Overview

Torque Converter

This transaxle uses a torque converter with the following elements:

- Impeller
- Turbine
- Reactor
- Torque converter clutch (TCC)

For component information, see Initial Inspection and Diagnostic Overview.

Planetary Gearsets

Operation of this transaxle involves the use of the following planetary gearsets:

- Front
- Center
- Rear

Apply Clutches

This transaxle uses the following clutches to operate the 3 planetary gearsets:

- Forward (1, 2, 3, 4) clutch
- Low/reverse clutch
- Low one way clutch (OWC)
- Direct (3, 5, R) clutch
- Intermediate (2, 6) clutch
- Overdrive (O/D) (4, 5, 6) clutch

For information about planetary gearsets or the apply clutches, see Mechanical Components And Functions.

Hydraulic System

The hydraulic system of this transaxle consists of the following components:

- Transmission fluid pump with filter
- Transmission fluid filler tube with transmission fluid level indicator
- Main control assembly (valve body and solenoid body)

For component information, see Hydraulic System.

Electronic Operation

The PCM controls the operation of the transaxle with the following solenoids:

- Line pressure control (LPC) solenoid
- Shift solenoid A (SSA)
- Shift solenoid B (SSB)
- Shift solenoid C (SSC)
- Shift solenoid D (SSD)
- Shift solenoid E (SSE)
- Torque converter clutch (TCC)

For solenoid information, see Transaxle Electronic Control System.

Park Position





Mechanical Operation

- Park pawl engaged, holding the final drive assembly stationary
- Low/reverse clutch applied

Planetary Gearset Operation

- Front planetary gearset driven components:
- None

Center planetary gearset driven component:

- Sun gear

Rear planetary gearset driven component:

- None

Front planetary gearset held component:

- Planetary carrier assembly (splined to final drive assembly, held stationary by park pawl)

Center planetary gearset held component:

- Center ring gear (splined to rear planetary carrier)

Rear planetary gearset held components:

- Planetary carrier
- Rear ring gear (splined to front carrier)

Park Position Clutch Application Chart





For component information, see Mechanical Components And Functions.
Park Position Power Flow






Hydraulic Operation

Line pressure hydraulic circuits:

- Line pressure from the pump is supplied to the main pressure regulator valve, low reverse/456 regulator valve, manual valve, solenoid regulator valve and control pressure regulator.
- Line pressure is controlled by the position of the main pressure regulator valve.
- The position of the main pressure regulator valve is controlled by varying pressure from the LPC solenoid through the VBS LINE circuit.

Torque converter circuits:

- Regulated line pressure from the main pressure regulator valve is directed to the TCC control valve through the CONV FD hydraulic circuit.
- When the TCC is released, CONV FD pressure is directed to the TCC RELEASE circuit by the TCC control valve. Pressure from the TCC RELEASE circuit releases the TCC.
- Fluid from the TCC RELEASE returns to the TCC control valve through the TCC APPLY circuit.

Cooler and lubrication hydraulic circuits:

- The TCC control valve directs fluid from the TCC APPLY circuit (return circuit from the torque converter when the TCC is released) to the COOLER FD circuit.
- In the COOLER FD circuit, transmission fluid flows through the transmission fluid cooler or the thermal bypass valve to the LUBE circuit in the input shaft to supply lubrication to the transaxle.

Solenoid hydraulic circuits:

- The LPC solenoid applies varying pressure to the main pressure regulator valve through the VBS LINE hydraulic circuit. The LPC solenoid regulates line pressure by controlling the position of the main pressure regulator valve.
- SSD applies pressure to the low reverse/456 regulator and latch valves to apply the low/reverse clutch.
- SSE applies pressure to the clutch control bypass valve to position the valve to direct regulated line pressure in the CBR1/C456 circuit to the low/reverse clutch.

Clutch hydraulic circuits:

- Line pressure from the pump is supplied to the low reverse/456 regulator valve. To apply the low/reverse clutch, SSD supplies varying solenoid pressure to the low reverse/456 regulator and latch valves. As the low reverse/456 regulator valve moves, it supplies the clutch control bypass valve and low reverse/456 latch valve with regulated line pressure through the CBR1/C456 circuit. The latch valve directs the regulated line pressure to the opposite side of the regulator valve through the CBR1/C456 FDBK circuit for gradual low/reverse clutch engagement.
- Regulated line pressure at the clutch control bypass valve in the CBR1/C456 circuit is directed to the low/reverse clutch through the CBR1 circuit to apply the clutch.

For hydraulic circuit information, see Hydraulic Circuits.