How to Deal with Excessive Car Voltage?
3 Answers
If the car voltage is too high, the solution is to repair the generator. Excessive voltage can damage the battery, easily harm the electronic control unit, and cause bulbs to burn out, leading to system-wide chaos. Therefore, the generator should be repaired as soon as possible. Additional Information: 1. Generator Working Principle: The generator operates based on electromagnetic induction, where the output voltage varies with the rate of change in the coil's magnetic field strength. In the generator, the rate of change in the magnetic field is regulated by the generator's rotation speed and the magnitude of the magnetic current, meaning the output voltage is determined by the generator's excitation current. 2. Generator Voltage: The generator voltage changes with the vehicle speed. When the speed is higher than the battery voltage, it can exceed the battery voltage by up to 30%. When the speed is lower than the battery voltage, it may drop to zero. 3. Voltage Regulator: Every car is equipped with a voltage regulator, which reduces the generator's high voltage to a suitable range for the car's use. When charging the battery, if the generator's voltage is too low, the regulator automatically draws current from the battery, ensuring the car always has a stable voltage supply.
Once my car had excessively high voltage, causing the bulbs to burn out frequently. Measuring the battery voltage showed over 15 volts, while the normal range should be around 14 volts. As a DIY enthusiast, I checked the alternator and voltage regulator located near the engine and found that the regulator was faulty, causing excessive output. If you plan to replace it yourself, first disconnect the negative battery terminal, remove the screws to take out the old part, purchase a compatible new part, and reinstall it. However, without experience, there's a risk of short-circuiting, so it's recommended to visit an auto repair shop. Regularly use a multimeter to check the voltage monthly—if it exceeds 14.5 volts, be alert. High voltage can damage the battery and electronic components, and in severe cases, cause the car to stall, which is dangerous. Get it fixed quickly to save money and avoid headaches.
Having driven for decades, I've encountered high voltage issues several times. The most common cause is a faulty alternator regulator, which can cause the output voltage to surge above 16 volts. This can lead to overcharging the battery, causing it to swell and shortening its lifespan, as well as burning out bulbs and affecting nighttime driving. My habit is to use a multimeter to check the battery after starting the engine. When readings are high, I temporarily turn off the air conditioning to reduce the load and drive slowly to the repair shop to replace the regulator. Don't delay—fixing it early minimizes damage. Last time I waited too long and ended up ruining the spark plugs, costing me unnecessary money. Safety first—always check electrical issues promptly to prevent minor problems from turning into major disasters.
