Trunk Lamp: Description and Operation

CIRCUIT OPERATION
The trunk lamp uses a switch located in the trunk latch which is case grounded. The switch is normally OPEN. When the trunk is opened, the switch CLOSES, completing a path to ground on circuit G78. The M1 circuit provides power to the lamp, and is HOT at all times.

Circuit G78 is spliced and provides an input to the instrument cluster indicating the trunk is ajar.