Skip the auto shop - Our mechanics make house calls

Q: A new battery will not hold charge overnight. alternator is not the problem / 2 mechanics checked.

asked by on

I have a new battery that will not hold a charge overnight. The alternator is not the problem and it was checked by 2 mechanics. The battery continues to drain overnight and needs a jump start everyday. could it be the wrong battery?

My car has 145000 miles.
My car has an automatic transmission.

Hello. If the battery continues to drain overnight despite recent replacement, then there might be some sort of electrical short or malfunction somewhere on the vehicle that is draining the battery. A good battery should hold a charge overnight without any issue. A simple load test should be able to determine if the battery is good or not.

There is also the possibility that you may have the incorrect battery. Your vehicle uses a 4.6L V8, and has a considerable amount of electronic accessories, and will experience all sorts of issues if the incorrect battery is used. I would verify that the battery is the correct size, and able to hold a charge, and then move on to examining the possibility of an electrical short. If you need further assistance with this, a certified technician from YourMechanic can inspect the battery firsthand to pinpoint the problem and make appropriate repairs.

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
  1. Home
  2. Questions
  3. A new battery will not hold charge overnight. alternator is not the problem / 2 mechanics checked.

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: heating/cooling and fan

You likely have a low coolant problem. When your coolant level isn't correct your air won't blow at the right temperature. However, it's also possible that your heater core isn't working properly. It may just be clogged and need to...

Q: I put new alternator, brought new battery crank car battery gauge do not go any further than half and start dropping while driving

You can verify alternator drive belt tension and measure charging system output at the battery posts. If the voltage output at the battery is with the required specification (roughly 13.8 to 14.4 volts but varies by model), check the condition...

Q: Why is my transmission fluid leaking?

Generally, there are only a few places for leaking transmission fluid to go to since it does not burn off inside the transmission, unlike motor oil inside an engine. You have already ruled out the possibility of an external leak...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
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...