Dome Lamp: Description and Operation

Voltage is applied at all times through fuse 14 to the ceiling light. With the ignition switch in RUN, voltage is applied through fuse 23 to the door open indicator light.

When you open a door and the ceiling light switch is in the DOOR position, a ground path is provided through the closed door switch, and the ceiling light goes on. With the doors closed you can turn on the ceiling light by turning its switch ON. The door open indicator light is also grounded through the door switches and the indicator lights.