When the gear selector lever moves to the Neutral (N) position from the Reverse (R) position, the following changes to the hydraulic and the electrical systems in the transmission occur:

Manual Valve

Mechanically controlled through the gear selector lever, the manual valve directs line pressure into the PRND43 and the PRND4 circuits. PRND4 fluid then passes around a valve land and enters the PRN fluid passage.

Automatic Transmission Manual Valve Position Switch

Line fluid pressure, acting on the diaphragms of the PRND43 and the PRND4 pressure, closes the switches thereby completing their circuits. At the same time, reverse fluid pressure exhausts at the manual valve. This action allows the reverse pressure switch to open its circuit to the PCM. The sequence of open and closed switches at the automatic transmission manual valve position switch assembly provides the input data to the PCM, indicating the position of the manual valve.