Ignition Switch On (Engine Off) Mode

IGNITION SWITCH ON (ENGINE OFF) MODE
When the ignition switch activates the fuel injection system, the following actions occur:
1. The Powertrain Control Module (PCM) determines atmospheric air pressure form the MAP sensor input to determine basic fuel strategy.
2. The PCM monitors the engine coolant temperature sensor and throttle position sensor input. The PCM modifies fuel strategy based on this input.

When the Ignition key is in the "on" position and the engine is not running (zero rpm), the auto shutdown relay and fuel pump relay are not energized. Therefore, voltage is not supplied to the fuel pump, ignition coil, and fuel injectors.