Q: I can't figure out why my car won't turn over without a jump even though the battery is fully charged.

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My car runs very well except that it needs to be jumped in order to start the engine. As long as the cables are attached to the battery, it will turn over without hesitation.

Once running I can drive the car all day long but as soon as I take the key out, the car won't turn over again (I hear one weak whine and then nothing).

It has a new alternator and the new battery seems to be holding a nice charge as well. When the engine is off, the accessories all function properly (ie. lights are bright, radio is loud, ect). Everything except for the seat belt warning which will not turn off even when the seatbelt is properly engaged.

Any troubleshooting advice would be greatly appreciated!

-thanks-

My car has 60000 miles.
My car has an automatic transmission.

If the engine cranks fine as soon as you connect jumper cables then you most likely have corrosion on the inside of the battery clamps where they touch the battery post. You should disconnect each battery clamp and clean them. Your engine should now crank over fine. I would recommend having the battery and charging system tested to make sure it is charging good and any problems are addressed. The seat belt system will need to be diagnosed by a mechanic in person in order to properly diagnose the seat belt light stays on.

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