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Q: Alternator

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Battery light kept flashing but battery was working fine. Friday I was driving and the dashboard went blank and truck felt like I was losing power and was going to die. I made it home and it did stop running.
My car has an automatic transmission.

The most likely cause is that the alternator has stopped charging. You would need to recharge the battery if it is dead, start the truck, and with a volt meter measure the voltage across the battery to see if the voltage is above 13.5 volts. If the alternator is not charging, it will be at or below the voltage you started with after charging the battery. Now check the voltage of the big wire to the back of the alternator with the engine off, to make sure you have battery voltage to the wire. If you do, then the alternator is most likely bad and will need to be replaced.

Never try and disconnect the battery while the engine is running to see if the alternator is charging. This may burn out electrical components like the computer. I’d recommend having a mechanic accurately diagnose your battery issue so the necessary repairs can be made.

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