# Battery not charging but alternator is ok?



## Rascal (Dec 16, 2006)

A while back you guys gave me help/advice with changing the alternator on my fathers 91 NX2000. After swapping in a reman, things seemed ok. Later I talked to him and he said that the battery still isn't charging.

I went and checked it using a voltmeter and it was putting out 14-15 volts, so it seemed ok. 

His concern is that either a fuse in the charging system is bad or that the alternator is putting out the needed amperage to charge the battery. Electrical is my weakness, so even after looking at the manual, I don't know where the fuse is or if I can check amperage output with some fancy testers. My thoughts is that if it is putting out voltage (measured at the battery terminal), then amperage should be ok, but I'm just not sure.

Any thoughts?


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## Pretty White (May 6, 2002)

How about the battery being weak and not holding a charge. That is completely possible that under load the battery dies or leaks down at night.


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## Rascal (Dec 16, 2006)

Pretty White said:


> How about the battery being weak and not holding a charge. That is completely possible that under load the battery dies or leaks down at night.


Hopefully not as it is a new battery, just a couple of months old.

I should add that I'm not convinced that the battery isn't charging, however my father is. Since he's pushing 80, his mind isn't easily changed once he has something in his head.

The reason he believes it isn't charging is that when he connects a battery charger (something he does about every other day), the needle rests at about 3, while with a voltmeter, it shows a solid 12 volts. After just a short time on the charger, the needle points to 0 and he is happy. The logic that it isn't charging comes from the initial reading of 3.

My argument that with the car on, the voltage reading at the terminal is about 14.5 isn't enough to convince him about it not charging the amperage - I have no clue about this.

After checking things out, we drove the car for about 30 minutes with the lights on and checked the voltage - it was fine and the car started fine. Again, not enough to convince him.

Does anyone know where the inline fuse for the positive battery cable is located? I assume it is close to the battery terminal, however I didn't notice it, just some sort of red connector.

No lights on the dash come on, and the output of the lights seems ok, revving the engine doesn't seem to have an effect on their brightness either way.

Thanks!


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## i r teh noobz (Apr 26, 2007)

My Toronado had a problem like what you describe. I changed my battery and my alternator at the same time, and kept having charging problems. My battery ended up being defective.


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## UkeeJay (Jun 26, 2007)

get your hands on a battery load test and see if the battery passes the test.


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## i3ulldog (Oct 29, 2006)

Rascal said:


> A while back you guys gave me help/advice with changing the alternator on my fathers 91 NX2000. After swapping in a reman, things seemed ok. Later I talked to him and he said that the battery still isn't charging.
> 
> I went and checked it using a voltmeter and it was putting out 14-15 volts, so it seemed ok.
> 
> ...


What in gods name are you trying to say? the car has 13 - 16v on the battery when running... its obviously charging and the alternator is doing its job. so why are you so concerned with checking fuses... I'm still scratching my head trying to figure out what the problem is here? Car runs, starts... so whats the problem?


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## MisterRx (Feb 8, 2006)

Maybe the dashboard light is defective. I herd a friend had instrument panel lights malfunctioning on NX2000.


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## MADNISS (Aug 6, 2005)

My car has the very same problem the car starts very good , drives very good but when ever I remove the battery cables the car just dies out which suppose to mean that the alternator isn't charging but while the car is on the tester reades 14.5 volts can someone help us out here.
Because I get dead battery sometimes


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## UkeeJay (Jun 26, 2007)

*check draw!*

check to see if there is too large of a draw on the battery when everything is shut off, the key is out of the ignition. if there is then something is draining the battery slowly. find it and fix it


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## tyronesk (May 19, 2018)

*battery dead*



UkeeJay said:


> check to see if there is too large of a draw on the battery when everything is shut off, the key is out of the ignition. if there is then something is draining the battery slowly. find it and fix it


My battery on my 2004 Nissan maxima won't hold charge I changed battery and alternator and rewired aftermarket radio system still battery won't stay charged please help thanks in advance


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## smj999smj (Jan 1, 2006)

Assuming the charging system voltage is ok and the battery is good, the next thing to do would be to have a parasitic draw test performed; there should not be more than a 50 milliamp draw on the system with the ignition switch "off." If you do, you need to do some testing to find out where the draw is coming from. Most usually remove fuses one at a time until the draw goes away or falls into acceptable range. If the problem didn't happen until the aftermarket stereo was installed, that may be a good place to start.


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## profilehair012 (Jun 13, 2018)

Thanks for sharing it.


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