Skip the auto shop - Our mechanics make house calls

Q: Dead Battery again

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car runs hot - 1996 Chevrolet Blazer

Hello. If your vehicle is running hot then you need to make sure you do not let it get too hot or engine damage will result. You'll need to find out if the cause is due to a leak, water...

Q: My car has a rough idle and misfires once its warmed up

Hi, and thanks for contacting YourMechanic. First of all, the mass air flow (MAF) sensor requires its screen; the air registering through the sensor is monitored with the elements in the screen. By removing the screen, you actually destroyed the...

Q: Car stalls after it runs for about 1 min

Hi There, It sounds like you may have a dirty or failing idle air control valve causing your engine idle to fluctuate and eventually stall. The idle air control valve is a small valve on the engine's intake system that...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.