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Q: I changed the battery and alternator but for some reason the battery isn't charging what could be the issue

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Got a brand new battery and new alternator however the battery isn't charging the car turns on and is running but it's not getting the full charge

My car has 160000099000 miles.
My car has an automatic transmission.

Check the fuse 65 in the main engine fuse box, it is a 7.5 amp fuse. Then check the main fuse A, a 120amp fuse. If both of these fuses are good then you will have to check them for power to see if they have battery voltage. If they do then the alternator should be charging. If either one of them is blown then replace the fuse and recheck the system for charging. You should have battery voltage with the key in the on position at all the wires of the alternator except the black ground wire.

If all the tests check out then the starter is defective if you still are not getting a charge. Make sure your battery cables are all good and not corroded. The ground wire should be grounded on the front of the engine.

If you need some assistance with these checks, consider YourMechanic, as a certified technician can perform these inspections and properly diagnose your battery issue. An accurate repair can then be made once the issue has been pinpointed. Good luck.

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