See Figures 1, 2, 3 and 4
Fuses protect all the major electrical systems in the truck. In case of an electrical overload, the fuse melts, breaking the circuit and stopping the flow of electricity.
If a fuse blows, the cause should be investigated and corrected before the installation of a new fuse. This, however, is easier to say than to do. Because each fuse protects a limited number of components, your job is narrowed down somewhat. Begin your investigation by looking for obvious fraying, loose connections, breaks in insulation, etc. Use the techniques outlined at the beginning of this section. Electrical problems are almost always a real headache to solve, but patience and persistence, coupled with logic, usually provide a solution.
The amperage of each fuse and the circuit it protects are marked on the cover of the fuse box, which is located under the instrument panel next to the steering column on but 1970-71 trucks where the fuse box is in the engine compartment on the firewall.NEVER USE A FUSE OF HIGHER AMPERAGE THAN RECOMMENDED
See Figures 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and 17
The turn signal and four-way hazard flashers are located under the instrument panel on opposite sides of the steering column. The turn signal flasher is the larger of the two. Replacement is made by unplugging the old flasher and plugging in the new one. Later model pickups may combine the two flashers into one.
Relays are used for the horn, headlights, wiper, heater, choke heater, catalyst floor sensor, air conditioner compressor, and transmission switches, although obviously not all relay are used on all models. All relays used are grouped together, and mounted on the right fender in the engine compartment.