Ignition Switch: Description and Operation

The Ignition Switch sends both "START" position and "ON" position signals to the ECU.

When various other parameters have been met, the ECU utilizes ignition "ON" as the signal to active the airflow sensor burn-off control system.

The ECU utilizes the "START" signal (engine cranking) in its calculations for controlling these outputs:

^ Fuel injection quantity and timing
^ ISC valve
^ Pressure regulator control solenoid valve
^ A/C relay/cut-off
^ Ignition timing control (igniter)