Q: Changed out the alternator and battery. Car will not start without a jump.

asked by on

Changed alternator, and battery and will not start without a Jump What will cause the battery not to charged back up. the car was driven 3,2 miles and was cut off for 20 minutes then then would not start back up

My car has 146000 miles.
My car has an automatic transmission.

This may be a sign of a failing voltage regulator. This is a unit that regulates the charging of the battery by the alternator. Often times this will result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery.

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.

In either case, I would recommend having an expert from YourMechanic come to your location to diagnose and properly diagnose and test your vehicle’s charging system.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Changed out the alternator and battery. Car will not start without a jump.

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: Dodge Ram pinion nut recall

Hi there. A loose pinion nut could definitely cause premature wear on the pinion bearing as there would not be sufficient preload on the bearing to maintain proper contact with the race. As for whether or not this would be...

Q: Number 3 cylinder misfire..antifreeze leak through thermostat housing..

Hi there. The thermostat leak should be easy to solve for a professional mechanic to repair, as they'll replace the thermostat housing itself during a thermostat replacement. The misfire issue should be inspected by a mobile mechanic by having them...

Q: Lexus IS 250 2010 electrical problems

I have checked all the recalls and technical bulletins for this vehicle and there are no known issues that can cause the battery to go dead in 3 three days. I would suggest you observe the vehicle in the dark...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.