Inhibitor Switch (A/T)

Inhibitor Switch:

The Inhibitor Switch (also referred to as neutral safety switch) signals the ECU as to transmission operating range and prevents starting the vehicle except in "P" or "N" positions.

In addition, the ECU utilizes gear position input from the inhibitor switch in its calculations for these outputs:

Fuel injection quantity
Idle speed control
Purge control
A/C cut-off
Igniter (timing control)
Pressure regulator control