For 1990-2009 cars

When the shift lever is in Neutral (N) position, the hydraulic and electrical system operation is identical to Park (P) range. But, if Neutral is selected after the vehicle was operating in Reverse (R), the following changes would occur in the hydraulic system:

### Reverse Clutch Release

Manual Valve: The manual valve is in moved to the Neutral position to blocks line pressure from entering the reverse fluid circuits. The reverse fluid circuits open in manual valve to drain fluid.

Reverse Clutch: The reverse clutch fluid is drained from reverse clutch to the #1 ball check valve to release the reverse clutch.

#1 Ball Check Valve: The reverse clutch fluid goes against #1 Ball Check Valves, and flows into reverse lockout fluid circuits. Reverse lockout fluid flows into reverse lockout valve, and then flows into reverse fluid circuits.

Reverse Lockout Valve: The reverse lockout fluid flows into reverse fluid circuits through reverse lockout valve, then flows to manual valve, and is drained from here.

Line Boost Valve: The reverse clutch fluid is drained from line boost valve, so that line pressure return to normal operation range of Park, Neutral and Overdrive.

### Low and Reverse Clutch Releases

Important: When drained, fluid is allowed to go through the valve bore bypass to ensure clutch release quickly. This prevents the friction material drag to cause High fluid temperature or damage to clutch.

Important: Shift Solenoid Valve should be Off in Park, Reverse and Neutral. This is the normal status when vehicle is stationary or moving slowly. But TCM will change the state of shift solenoid valve according to the vehicle speed. For example, if Neutral is selected in 2nd gear, then shift solenoid valve will remain in 2nd gear. But when the manual valve is in Neutral, the line pressure is prevented, D432 fluid is drained and the transmission will shift to Neutral.

Low and Reverse Clutch: Low and Reverse Clutch or Reverse lockout fluid is drained from the outboard area of Low and Reverse Clutch piston to #8 Ball Check Valve. Reverse lockout fluid can be drained from the inside of Low and Reverse Clutch piston through valve bore #12. The draining of fluid allows Low and Reverse Clutch Release.

#8 Ball Check Valves: Low and Reverse Clutch or Reverse lockout fluid goes against the #8 ball check valves to Low and Reverse Clutch fluid circuits, flows into reverse lockout fluid circuits, and then is drained from the manual valve with reverse clutch fluid.

#### Neutral - Engine Running