Neutral Safety Switch: Description and Operation

PURPOSE
Signals the Powertrain Control Module (PCM) of gear selection.

OPERATION
On vehicles equipped with automatic transmissions, the [1][2]park/neutral switch indicates if the transmission is in NEUTRAL, PARK, or a DRIVE GEAR. Based on input from this switch the PCM will adjust fuel injector pulse width, ignition timing advance, and idle speed.

CIRCUIT OPERATION
When closed, the [1][2]PARK/NEUTRAL position switch provides an input to the Powertrain Control Module (PCM) on circuit T41. The T41 circuit is spliced and provides a ground path for the engine starter relay, and an input to the Transmission Control Module (TCM).