Voltage Regulator

What is a Voltage Regulator?

The voltage regulator on your vehicle controls the amount of electricity produced by the alternator. This protects your vehicle's charging system from exposure to excessively high voltage levels that could damage the battery or other electrical components in the system. Many modern vehicles have the voltage regulator built into the alternator, but older vehicles may have a standalone voltage regulator mounted in the engine compartment or elsewhere. With the help of the voltage regulator, the voltage flowing through the charging system remains at a consistent level, ensuring your engine and onboard electrical systems perform as they should and that the battery does not overcharge. Because your vehicle's battery, lights, and many other important safety features are controlled electronically, your vehicle depends on the voltage regulator to keep the battery fully charged and to prevent fluctuations in alternator output at varying RPMs from causing electrical surges. If you are experiencing dim dashboard lights or headlights, frequent light bulb replacements, engine stalling, a dead battery or a battery that won't charge at all, or a failing instrument cluster with inaccurate readings, your voltage regulator could be to blame. A voltage regulator that allows the battery to overcharge may also cause electrolyte to evaporate from the battery case, and this can lead to sulfur smells while driving. If you suspect your voltage regulator may not be working, you can use a voltage or electrical tester to test your vehicle's voltage readings, or visit O'Reilly Auto Parts for free alternator and charging system testing. This can help narrow down the source of the problem and allow you to determine whether the alternator, voltage regulator, or battery may need to be replaced. O'Reilly Auto Parts carries replacement voltage regulators and charging system parts for most vehicles to help you make a complete repair.