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Q: How do you know if you have a bad battery or a bad alternator if your car won't crank all the way up

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When cracking my car all lights come on inside the dash but my engine wouldn't come on after awhile I began trying to get a jump I did this about three times nothing would happen so I let my car sit and tried again but this time my lights wouldn't come on at all! I again tried getting a boost but my car wouldn't crank I than moved around the negative post and my car lights will come on than quickly turn off help please!?
My car has an automatic transmission.

The lights in your car will take a lot less power to operate than the starter to turn over the engine. You should take off the battery connections and clean them with baking soda and water, then reinstall and tighten them. If it was the connections then you may be able to start the car now if the battery is good. After the car is running then look at the gauges to see if all are normal.

If your car is still unable to start after doing this, contact a certified mechanic who can ensure that your battery is operating as it should.

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