What causes bad voltage regulator?

They usually fail because they’re under rated for the constant current draw. Running the motor with the battery disconnected – or even a poor contact on the battery terminals – can also blow them. The voltage regulator controls the field current applied to the spinning rotor inside the alternator.

How do you tell if an alternator is overcharging?

Symptoms of Your Car Alternator Overcharging:

Car Battery Voltage Gauge Reading is High. You notice a high voltage reading on your cars vehicle’s dashboard.
Car Battery Gets Hot When Charging.
Your Headlights Burn Out Quickly.
Your Car Battery is Bulging on Sides.

How do I know if my battery is overcharging?

Use A Multimeter When the vehicle is started, without the introduction of a load (the lights or air conditioner), the volts will usually rise to an average of 14 volts. If the multimeter reads at more than 14.8 volts, then this can be considered as overcharging.

What happens when the alternator is overcharging?

Alternators that overcharge will typically produce excess voltage to the battery, making the battery case swell up, become very hot and lose its electrolyte through boiling. Improperly jump-starting the vehicle can send a surge through the battery that destroys one or more cells in the battery or shorts it out.

Can I drive with an overcharging alternator?

Overcharging causes excessive heat to be produced in batteries which can cause explosion, melt-down, boiling away of acid, premature corrosion of electode plates within the battery cause premature failure of the battery, the elctrodes can warp inside the battery and short out the battery and take all the electronics in …

Is 15 volts too high for alternator?

So, to answer your question, Yes, 15 volts is too high. Most car alternators, that normally recharge your battery after every start, and provide power while the engine is running, are normally voltage regulated to about 13.8 to 14.0 volts.