Circuit/System Description

The engine control module applies 5 V to the hood ajar signal circuit and monitors the voltage to determine the position of the hood. The hood ajar switch contains a multiplexed resistor. This resistor will vary the voltage seen by the engine control module by pulling down the applied voltage based on the position of the switch. The terminals at the switch can be identified by letters or numbers. Letter A is number 1, letter B is number 2, and letter C is number 3.