Circuit Description
WARNING: This page is about a different car, the 1995 Oldsmobile Ninety-Eight and 1995 Buick Park Avenue. However, it is still accessible from the selected car via links, so may be relevant.
Transmission range switch is part of Transmission Mounted Neutral Start Switch (TMNSS) mounted on transaxle assembly. Transmission range switch is a multi-signal switch that sends information, relative to gear selector position, to PCM. PRNDL input consists of 4 discrete circuits to pull 4 PCM voltages low in various combinations to indicate each gear range. Voltage level of each of circuits is represented as low equals grounded circuit and high equals open circuit. The 4 states displayed represent decoder parity, "A", "B"and "C" respectively.