Power and Ground Distribution: Description and Operation

Electrical power for the car is provided by the Generator when the engine is running. The schematic diagram shows how each circuit gets its power. For more details about the Generator and connections to the Battery and Starter, see CHARGING & STARTING SYSTEM.
The car's Power Distribution System consists of Fusible Links, Fuses, Circuit Breakers, the Light Switch, and the Ignition Switch. Fusible Links are short pieces of wire several sizes smaller than the circuit wire to which they supply power. They are covered with special high-temperature insulation. When conducting a dangerously high current, they will melt and stop current flow. They are designed to protect the car's electrical system from electrical shorts where it is not protected by the Circuit Breaker and Fuses.
See FUSE BLOCK DETAILS for complete distribution of power from each fuse to the individual components that it serves.
The ignition Switch has six positions, four of which have detents. The BULB TEST position is just after the RUN position and just before the START position. BULB TEST and START do not have detents.
Individual schematics show their fuses supplied from headings such as HOT IN RUN. The heading corresponds to the Ignition Switch position in which power is supplied to the circuit.