Transmission Position Sensor/Switch: Description and Operation

Neutral Gear Switch (NGS):

PURPOSE
The Neutral Gear Switch (NGS) detects when the manual transaxle is in the in-gear or neutral position and sends an input signal to the ECA. This is an engine load input used by the ECA in calculations for adjusting idle speed, ignition timing, air/fuel mixture, fuel pressure, purge flow, and A/C cutoff.

OPERATION
NGS is an ON/OFF switch that receives a 5 Volts reference from the ECA. When the switch is OPEN (transmission in GEAR), the ECA senses voltage. When the switch is CLOSED (vehicle in NEUTRAL), the ECA senses no voltage.