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Q: Dead Battery again

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My truck was running great but one day it would not turn over. Just 12 hrs after I last drove it, it wouldn't start. 'Your Mechanic' came out found the fuel pump was no good. 'Your Mechanic' replaced the fuel pump. The next day. The battery was dead. 'Your Mechanic came back out and checked the wiring and the alternator and belts, charged the truck, re-ran a new main wire(?). We let the truck run for about 30 min. Truck was dead again after 1 hr. Charged it, took to AutoZone (where I bought the battery less than a year ago) and they said it's not charging and it could be the alternator. 'Your Mechanic' came again and replaced the alternator which also was less than a year old. "Belt are less than a year old. "So must be your battery" Battery was replaced and now again a dead truck. 3 times out, 3 x $70 fee, new fuel pump, new alternator and new battery still same dead truck?

My car has 10700 miles.
My car has an automatic transmission.

You may have a failing voltage regulator that could be allowing the alternator to supply too much or too little amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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