Sometimes, what people bother so much about turn out to be problems whose solutions are extremely obvious. This conversely means that checks for electrical problems in cars should start at the most obvious locations; the battery being a good example. Sometimes, a case of a car failing to 'start' or something of that sort could be simply as a result of an electrical contact breakdown at the battery. Here all that is required in the name of auto electrical repairs is something as simple as filing the terminals that connect the car to its battery.
When doing auto electrical repair, the first vehicle component your should acquire knowledge about is the car battery. Even though the battery only store 12 volts, it is the electrical source of the entire vehicle. You will not be able to start your engine without the battery. In addition the auto battery helps to operate all the electrical accessories installed on your motorcar. An auto battery should last 3-5 years in average climates. Extreme hot or cold climates however, will reduce this to only 2-3 years.
An old oxygen sensor (say, 90,000 miles or more) may still work well enough that it doesn’t trigger the check engine light but could still hurt fuel economy. Engine performance can also be reduced by more serious internal problems, such as valves that don’t seat properly or worn piston rings, or by restrictions in the exhaust system. Because the same symptoms can suggest different problems, and there are often several possible causes and cures, it’s better to consult a professional mechanic than to try to be one if you have neither the experience nor the right equipment to diagnose drivability problems. In short, rather than ask for a tune-up, tell a mechanic what you’re experiencing and ask him or her to find the cause.
Bulbs, though, are probably No. 1 on the replacement list because they're used so much and because there are so many of them. Most cars, for example, have at least three bulbs and usually more on each side for brakes, taillights, backup lights, turn signals and side marker lights. In front, there are headlights, maybe separate high beams, frequently daytime running lights and fog lights, turn signals, "parking" lights and side markers. Chances are that over time at least a couple of those will burn out or stop working because of corrosion or excessive jostling from rough roads.