Q: Alternator or Battery is not Charging

asked by on November 17, 2016

For instance, let's say the car died on me last night. Ok, I can let it sit over night and in the morning she fires right up with no hesitation. Then if I unhook the positive from the battery while she running, she dies instantly. And not to forget I just replaced the battery and alternator.

My car has 193000 miles.
My car has an automatic transmission.

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The first thing is that disconnecting the battery cable when the engine is running can damage the alternator and computer modules on the vehicle. This will cause voltage spikes that will burn electrical circuits out. With the description of the problem you gave you most likely have a defective alternator or a charging circuit problem and should have have the charging system checked. to see if the alternator is not charging or there is another issue with the electrical system. I would recommend having a mechanic like one from YourMechanic come to you and diagnose the charging system and if needed to replace the alternator and check the system for any other possible problems from disconnecting battery while engine is running.

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