The other, probably rated at about 20-30 amps, protects components not wired through the ignition — horns, interior lights and the cigarette lighter. Where a single fuse protects a number of circuits and keeps blowing, each circuit must be checked individually to discover which one is faulty.
The starter motor has its own heavy cable, direct from the battery. The ignition circuit furnishes the high-tension impulses to the sparkplugs; and the charging system includes the generator, which recharges the battery. All the other circuits are called ancillary (subsidiary) circuits.
Most car handbooks and service manuals include a wiring diagram which can be difficult to follow. The colour-coding, however, is a useful guide to tracing wiring.
The fuse box is often located in a cluster of components, as illustrated here. The box is shown with the cover off.