Q: Battery good, alternator good, brand new alternator cable, still not charging.

asked by on

I need help finding out what could be wrong with my charging system. One day my 2003 Expedition didn't start, got a jump start and took it to auto zone to check. Battery voltage was too low to test, so I took battery out and left it out overnight, next morning picked it up, they said battery was good and held charge. Put battery back in and took it for testing, their test said the voltage regulator was bad, so bought a new alternator, installed it, same thing, not charging. Took old alternator back so they could run a bench test, old alternator came back good. So I just recently replaced the alternator cable thinking maybe it was the cable... nothing, still not getting a charge. My multimeter is only reading the current volts on the battery while engine is running, reading 12.4 volts and slowly draining. I can't think of anything else. As far as I know, I don't know of any fuses or relays assigned to the charging system. Please help. Thank you.

My car has 190000 miles.
My car has an automatic transmission.

Hi There, The first diagnosis of the bad voltage regulator is likely the cause of your charging system not properly charging the battery. 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. 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 some cases when a battery is too weak or damaged, it may no longer hold a charge for any length of time, in which case the alternator may be doing its job, but the battery is just simply too weak to hold a charge. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose 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. Battery good, alternator good, brand new alternator cable, still not charging.

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: Do I need alignment after replacing front shocks and struts

Some vehicles have fixed front camber which is typically the only alignment criteria (measure) that would be affected by strut replacement. However, your vehicle does have adjustable camber settings and so, yes, the vehicle would have to be aligned if...

Q: My car has been sitting for 5 months, it starts but when I drive it it sputters and stalls, why is that?

You may need to add fresh fuel and then see if it runs better. If engine misfires then you may have fouled plugs and or bad coils. have computer tested for misfire codes to isolate the cylinder that is misfiring....

Q: Q: AC blowing out warm air again

If this happened right after the work was done then you either have a leak in the system that allowed the refrigerant to come out or there is an electrical issue. It is possible that this was overlooked if the...

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...