About Electrical Systems


AUTO REPAIR SERVICESAn electric generator that produces alternating current. The generator’s coil is rotated (by a turbine, motor, or other power source), and its circular path causes it to cut cross a magnetic field (set up by strong magnets), first in one direction, then the other, with each cycle. The electric potential induced in the coil by this motion thus alternates between positive and negative once with each cycle, resulting in alternating current.

This unit provides all the electrical power to operate the vehicle and is powered by the A drive belt. Excess power not needed by the vehicle is used to keep the battery at full charge.

This unit needs 12 volts to operate and delivers anywhere from 13 to 15 volts to the vehicle’s electrical system.


AUTO REPAIR SERVICESA battery is a man-made power cell used to generate electrical energy. This power source produces electricity to start the vehicle and to operate all 12-volt electrical accessories (e.g., lights, radio, alarms, starter) while the engine is not running.

Battery Service:

The battery is serviced by ‘topping off’ the fluid with distilled water, charging the battery, and performing a load test. If a battery is old, a charge may not suffice and you will likely need to buy a new battery. Note: Make sure to check your battery prior to the winter months to make sure that you are charged and ready for the cold weather.

Battery Terminals Disconnection During Service Work:

When servicing and repairing a vehicle manufactured after 1980, the manufacturer may require the disconnection of the battery cables as a step in the service or repair procedure. On most vehicles, after the battery cable has been disconnected the “Keep Alive Memory” (KAM) of the vehicle’s computer system usually is reset as a result of this. A vehicle may exhibit certain drive-abilty concerns or other concerns that may not have been apparent to the driver or the technician before a service or repair. I.E. A Vehicle may experience: idle fluctuation, higher than normal idle, lower than normal idle, engine stalling, transmission shifting concerns, fuel economy variations, service malfunction indicator lamp illumination immediate after or soon after the service or even a few days later, radios may not work; unless the code provided by the manufacturer is reentered, clocks may be inaccurate thus require resetting, radio preset buttons may have to be reprogrammed, seat positions may have to be reprogrammed, HVAC system doors operation may require recalibrating, instrument gauge readings may be inaccurate, etc.
“Battery Saver Tools” have been introduced to the automotive market to attempt in maintaining the KAM of a vehicle’s computer system during service. However, in some cases, due to the nature of a repair or service, the technician may not have the option of using this device. There are some repairs and services that the manufacturer of the vehicle actually requires the technician to reset the KAM as a part of the proper repair or service procedure.
To reset the KAM of a vehicle’s computer system it may be necessary to drive the vehicle several miles, or even days, under various operating conditions, speeds, temperatures, & loads. This may allow the various computer systems to relearn the values for optimum performance. Some vehicles may require special tools to force and accept a relearn.
In extreme circumstance the computer may not have the ability to relearn because of age, wear & tear, carbon build up, and degradation of various components. Inspection and testing of a system may be required to pinpoint the item that is hindering the system from relearning. Replacement of actual components may even be required to return the vehicle back to a normal operating condition.
Customers should always remember that the KAM may be reset when the battery cables are disconnected.


Most cars from the early eighties have some form of computer management, e.g., a central processor. Depending on the vehicle, it can control nearly every automated function.

Distributor Cap/Rotor:

AUTO REPAIR SERVICESSequentially distributes the spark received from the coil to each of the cylinders.The distributor handles several jobs. Its first job is to distribute the high voltage from the coil to the correct cylinder. This is done by the cap and rotor. The coil is connected to the rotor, which spins inside the cap. The rotor spins past a series of contacts, one contact per cylinder. As the tip of the rotor passes each contact, a high-voltage pulse comes from the coil. The pulse arcs across the small gap between the rotor and the contact (they don’t actually touch) and then continues down the spark-plug wire to the spark plug on the appropriate cylinder. When you do a tune-up, one of the things you replace on your engine is the cap and rotor — these eventually wear out because of the arcing. Also, the spark-plug wires eventually wear out and lose some of their electrical insulation. This can be the cause of some very mysterious engine problems.


AUTO REPAIR SERVICES-Current flows through the fuses to all electrical accessories.
-Each fuse can withstand a predetermined level of amperage and will burn out if that level is exceeded. This protects the electrical system from damage.
-Although a damaged fuse is not a welcome event, it is much more desirable than a fried component.





A solenoid is a coil wound into a tightly packed helix. In physics, the term solenoid refers to a long, thin loop of wire, often wrapped around a metallic core, which produces a magnetic field when an electric current is passed through it. Solenoids are important because they can create controlled magnetic fields and can be used as electromagnets. In the automotive field, solenoids are used as electromagnetic devices that convert electricity to mechanical functions such as engaging the starter or operating a fuel injector.

Spark Plug:

AUTO REPAIR SERVICESA device that screws into the combustion chamber of an internal combustion engine to provide a pair of electrodes between which an electrical discharge is passed to ignite the combustible mixture. The spark plug consists of an outer steel shell that is electrically grounded to the engine and a ceramic insulator, sealed into the shell, through which a center electrode passes (see illustration).

Spark Plug Wires

A wire with thick rubber insulation that carries the high voltage current from the ignition coil to the spark plug.

Starter System:

AUTO REPAIR SERVICESThe primary system consists of the ignition switch, coil primary windings, distributor contact points, condenser, ignition resistor and starter relay.

–┬áThe secondary ignition system consists of the coil secondary windings, distributor cap, rotor, plug wires and spark plugs.

– When you turn the ignition, electricity is sent to the starter. The starter produces energy that turns the engine over and starts the engine.