The electrical system is perhaps the most important support system of a car or truck. Without a properly working electrical system, gasoline engines would not run. Electricity provides the needed spark for combustion, plus the power needed for starting, lighting and signalling, instrumentation, safety devices and many other accessories that you use every day.
Electrical vs. Electronics:
There is often confusion concerning the terms electrical and electronic. “Electrical” refers to wiring and electrical parts, such as generators, lights, and voltage regulators. “Electronics” means computers and other black box type items used to control engine and vehicle systems. The electrical system of an auto mobile includes the ignition, starting, charging, and lighting systems.
Open circuit refers to when a circuit has a break in the wire. Without a completed path, current cannot flow and the load or component cannot work.
Short circuit refers to an unwanted current path. Short circuits cause an increase in current flow. This increase in current flow can burn wires or even components.
High-resistance circuits refers to a problem occurring when there is unwanted resistance in the circuit. The higher than normal resistance causes the current flow to be lower than normal and the components in the circuit are unable to operate properly.