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Q: Car keeps dying even though I jump it and the battery is less than a year old

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car keeps dying. Less than year old battery. Give car a jump. Car starts and drives maybe a mile and dies while driving. Keeps repeating.

A: Hello. This is not caused by the battery mo...

Hello. This is not caused by the battery most likely. The alternator may not be charging the battery and, after you jump start the battery, if the alternator is not recharging it, then the battery may be able to only keep the engine running for a few minutes before running out of power. You will need to have the battery completely recharged and load tested to make sure it is working properly even though it is only a year old.

Once the battery is recharged, then the alternator should be tested to see if it is charging normally. This is done with a battery/charging system tester or voltmeter with an amp probe. The alternator should be putting out about 13.5 volts and 80% of the rated amps output that it is rated at when the engine is running at 1500 RPMs. You should have an alternator rated at between 75 and 100 amps. This means if you are not getting over 60 amps output then the alternator needs to be replaced.

I recommend having a certified mechanic, such as one from YourMechanic, come to your location to determine why the battery will not hold a charge and replace the alternator if needed.

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