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Underhood Lamp: Description and Operation

CIRCUIT OPERATION
Circuit M1 from the fuse in cavities 19 and 20 in the Power Distribution Center (PDC) supplies battery voltage for the underhood lamp. A mercury switch in series after the lamp connects the lamp to ground on circuit Z1. When the hood is raised, mercury inside the switch moves to a position where it connects circuit M1 to ground circuit Z1, illuminating the lamp.