Q: Car Battery completely depleted for no reason

asked by on February 08, 2018

My cars battery is only a year old. I drive my car daily and tonight I went to get into my car, unlocked it with the remote ( it unlocked) and as soon as I put the key into the ignition all the lights came on for maybe 1/8th of a second and then the ENTIRE car was dead! like nothing worked. it wouldnt starts..no lights would work, the automatic locks wouldnt even work, I couldnt even pop the trunk with the remote! the whole car was 10000% dead. I had it jumped and it worked. what could be the reason for this?

My car has 78800 miles.
My car has a manual transmission.

Alternator Replacement $151.62 - $1237.14 Get a Quote

It sounds like you may have a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator charges the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator pulley. The voltage regulator is a unit that regulates the charging of the battery by the alternator and maintaining a certain amperage while the engine runs. When the alternator is not working properly, this may result in the battery quickly losing charge and the car losing all power. You may also notice a whining sound as a result of the bearings inside the alternator begin to fail. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

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