Transmission Position Sensor/Switch: Description and Operation

TRANSMISSION [1][2]PARK/NEUTRAL SWITCH - PCM INPUT

The [1][2]park/neutral switch is located on the transmission housing and provides an input to the powertrain control module (PCM). This will indicate that the automatic transmission is in Park, Neutral or a drive gear selection. This input is used to determine idle speed (varying with gear selection), fuel injector pulse width, ignition timing advance and vehicle speed control operation.