Circuit/System Description
WARNING: This page is about a different car, the 2007 Suzuki XL7. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) monitors the voltage input of the hood open switch signal circuit and the hood open closed switch signal circuit. With the hood open, the hood ajar portion of the switch is closed, grounding the Hood Ajar Switch Signal circuit from the BCM, and the hood closed portion of the switch is open. With the hood closed, the hood closed portion of the switch is closed, ground the Hood Closed Switch Signal circuit from the BCM, and the hood ajar portion of the switch is open. During proper operation, the 2 separate voltage signals at the BCM should never be at the same voltage with the hood opened or closed.