Q: Brake light battery light

asked by on December 10, 2016

Brake light and battery light flashing and headlights are dimming during this as well as the battery loses power . Checked all grounds and alternator was replaced 2 months ago alternator seems to be getting hot but test ok. Jist chanhed the betteey terminals. (BOTH)Not sure where to look or what to replace

My car has 170800 miles.
My car has an automatic transmission.

This may suggest a failing voltage regulator. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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