Charging problem??

[Slalom67]

My 2000 Explorer Sport| 4x4 | 4.0L SOHC Wouldn't accelerate while driving residential speeds today. I was able to idle it home, the power windows wouldn't work, or the ac. When I shut it off it wouldn't start again. The Battery which is 2 years old was completely dead. I pulled another battery, fully charged from another vehicle and it started right away, windows and ac working and no difficulties accelerating and driving normally. The alternator was changed 2 years ago. But my battery Gauge is only at 1/4. I am concerned that the battery is not charging. Does anyone have any ideas??

 

[Flash]

Could be corrosion on the battery terminals or cables.

If you have a volt meter the battery should read about 12 volts with the engine off and 13.8 with the engine running.

 

[koda2000]

Could be corrosion on the battery terminals or cables.

If you have a volt meter the battery should read about 12 volts with the engine off and 13.8 with the engine running.

actually, to be technical, a fully charged battery should read 12.6 volts (or more) with engine off and seeing 14.6 volts with the engine running is not unusual.

 

[Flash]

actually, to be technical, a fully charged battery should read 12.6 volts (or more) with engine off and seeing 14.6 volts with the engine running is not unusual.

12.6 volts is exactly about 12 volts.

 

[koda2000]

12.6 volts is exactly about 12 volts.

I wasn't correcting you, just being technical. 11.8 volts is also about 12 volts, but doesn't indicate a fully charged battery.

 

[Flash]

I wasn't correcting you, just being technical. 11.8 volts is also about 12 volts, but doesn't indicate a fully charged battery.

Was just kidding.

 

[Slalom67]

Flash, thank you for the quick response. I will check when I get home.

 

[fast_dave]

My 2000 Explorer Sport| 4x4 | 4.0L SOHC Wouldn't accelerate while driving residential speeds today. I was able to idle it home, the power windows wouldn't work, or the ac. When I shut it off it wouldn't start again. The Battery which is 2 years old was completely dead. I pulled another battery, fully charged from another vehicle and it started right away, windows and ac working and no difficulties accelerating and driving normally. The alternator was changed 2 years ago. But my battery Gauge is only at 1/4. I am concerned that the battery is not charging. Does anyone have any ideas??

The alternator could be fine - it's the internal solid state voltage regulator that frequently fails.

Spend 10 minutes, and take off your alternator.

Bring it to any of the "big box" auto parts stores to have them hook it up to their digital alternator tester - they do this for free.

A digital alternator tester will tell you within 30 seconds what the situation is.

 

[Flash]

The alternator could be fine - it's the internal solid state voltage regulator that frequently fails.

I've even replaced the brushes in an alternator and it's still going.
The brushes were part of the regulator.

 

[Slalom67]

Thanks fast Dave. Had the alternator tested today. Failed. Put in a new one and everything is working great!

 

[fast_dave]

Thanks fast Dave. Had the alternator tested today. Failed. Put in a new one and everything is working great!

Hey Slalom67!

I'm glad to been able to help you, as well as to give back to the forum

BTW - I don't know if they told you this at the parts store, but do not hook up the dead battery to the new alternator, as you could burn up the new alternator.

The completely dead battery needs to be thrown on a charger, and then hooked up to the new alternator.

 

[Slalom67]

Hi Dave..... Nope they failed to mention that! Guess they want to see me back soon! Although I did get the dayco with LT warranty. Didn't make much sense to me to try the new alternator with a dead battery so I fully charged it up before I put it in. Thanks agin for your help!

 

[fast_dave]

Hi Dave..... Nope they failed to mention that! Guess they want to see me back soon! Although I did get the dayco with LT warranty. Didn't make much sense to me to try the new alternator with a dead battery so I fully charged it up before I put it in. Thanks agin for your help!

No prob - it's always the little details that make all the difference

Welcome to the forum and good luck with your Ex!

PS - keep the LT warranty in your glovebox, and maybe the basics required for removal
Speaking from experience - about 10 years ago I had a Sears Diehard battery bought in the PRK "die hard" in a Sears parking lot in Oregon. Lucky for me I had my battery paperwork in the glovebox, and a Leatherman multi-tool in the center console...