You're charging system should be supplying voltage between 14.0-14.5 in most cases, sometimes higher, but never over 16.5 volts. If the voltage is still only 12.4-12.6 once the engine is running, then the charging system is not functioning.
A worn, loose, or damaged connector can cause a massive voltage drop. While an alternator can be an expensive piece to purchase, nothing could be more frustrating than buying one only to find out that the one you replaced was fine and another part was the problem.
Either case, the alternator will need to be removed, tested, and the wiring and fuses related to the circuit checked as well. If any testing or replacement of your alternator or charging system becomes too difficult of a job, consider visiting one of our Preferred Repair Shops in your area can help you diagnose and repair any faults in the charging system.
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Refer to the service manual for specific diagnostic, repair and tool information for your particular vehicle. Always disconnect the negative battery cable before servicing an electrical application on the vehicle to protect its electrical circuits in the event that a wire is accidentally pierced or grounded.
Sulfuric acid is caustic and can burn clothing and skin or cause blindness. Always wear gloves and safety glasses and other personal protection equipment, and work in a well-ventilated area.
Should electrolyte get on your body or clothing, neutralize it immediately with a solution of baking soda and water. Do not wear ties or loose clothing when working on your vehicle.
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After your vehicle starts, it is the alternator that provides electrical power and then also, maintains a charge on the battery. In fact, automobiles up to the 1960s used a generator (which produces electricity but does so differently with different internal parts) and some vehicle manufacturers (many in Europe) still refer to a modern-day alternator as a generator.
In simple terms, your car’s engine delivers power to the wheels. It receives mechanical energy from the pulley, which is rotated by the engine belt, and uses magnetism to generate alternating current.
Modern car alternators have a few essential components that allow them to do their job. Several of these precisely spaced windings work with the rotor to generate an alternating current.
It is supported on both ends with bearings and spins with the assistance of a pulley and drive belt. The rotor features an iron-core center that has a copper wire wrapped around it.
Energizing the wire with an electrical current causes a magnetic field with north and south poles to develop. It is an electronic component and is responsible for maintaining the charging system voltage within a specified range.
You should realize, though, that your alternator also has other parts, including a housing, bearings, brushes, and bushings. If this happens, you are apt to hear a loud, grinding noise coming from under your car’s hood.
Furthermore, if the alternator’s bearings are well past their prime, the belt may whine, chirp or squeal. Your vehicle may have an instrument readout that tells you how many volts the alternator is delivering.
Regularly inspecting the drive belt for signs of wear is a good way to ensure your alternator’s rotor keeps spinning properly. This will cause the alternator to not charge properly and can also lead to a dead battery or lit CEL on the instrument cluster.
The alternator has vent holes that allow heat to escape and help to prevent overheating. Because the consequences can be significant, you do not want to ignore problems with your vehicle’s alternator.
You may also cause additional damage to your vehicle by putting off essential alternator repairs. After all, a bad cell inside your battery can ruin your alternator.
If you have a vehicle that doesn’t get driven often, consider using a trickle-charger to keep the battery maintained during the downtime. It is important to note, an alternator should NEVER be used to charge a dead battery.
Many times, this is why both failure of the battery AND the alternator can occur within weeks of each other. If you think your vehicle’s alternator or battery may be suspect, you can seek out one of our preferred shops in your area to help.
If you want to come out on top, you cannot leave the health of your vehicle’s alternator to chance. By watching for common problems, you know when to repair or replace your alternator.