Skip the auto shop - Our mechanics make house calls

Q: Battery is not charging properly

asked by on

Battery keeps going dead but we took it to get tested and they said it was good

My car has 130000 miles.
My car has an automatic transmission.

A: This may be a sign of a weak battery, a fai...

This may be a sign of a weak battery, a failing voltage regulator or failing alternator. As you may know, the alternator is responsible for charging the battery while the engine runs by generating amperage and recharging the battery while the engine turns the alternator. The voltage regulator is a unit that regulates the charging of the battery by the alternator.

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. 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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Electrical fault

Getting your car broken into is a pain! Often the thieves do thousands of dollars of damage to your car to steal a hundred dollars worth of stuff. It can take a long time to sort everything out. It sound...

Q: Car won't turn over; clicking, grinding sound

The system would have to be checked to see if the alternator you put in shorted and killed the battery; I have seen new alternators kill a battery from being shorted inside them. It could also be that the battery...

Q: Clutch not disengaging

The first thing to check is to have someone push in the clutch several times to see if the clutch slave cylinder is pushing in the pressure plate inside the transmission. You can see this happening by looking through the...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...