Depending on the year that fuse boxes became important to you, you may never have noticed a car with only one fuse box. I’ll start this article with a brief historical introduction and then move on to the topic of one versus two fuse boxes.
Most cars made in the US or made by an American brand at one time only had one fuse box. In fact, until the late 1980s, the aforementioned cars had only one fuse box inside the car. Across the ocean, Japanese and European rivals had started using 2 fuse panels nearly a decade earlier. They had added a fuse box under the hood for engine related circuits. Back then, American manufacturers protected high-amperage circuits by using special wires called fusible links. These cables were designed to melt when experiencing an overload.
Today almost every car is designed and manufactured with 2 fuse boxes or panels, one inside the car and one under the hood. Although a specific fuse may be under the hood of one car, it may be inside the car in another. However, the general rule of thumb is that the interior panel includes fuses for the headlights, heater, radio, windows, seats, defroster, sunroof, etc. In other words, the interior panel will have fuses related to the car’s bells and whistles. On the other hand, the panel or box under the hood normally facilitates the fuses related to the engine, such as the ignition, the injectors, the fuel pump, the brake system, etc.
For more information on selling your car, see Why does my car have two fuse panels?