battery or alternator?

Holik95

New Member
Aug 14, 2005
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Granite City,IL
Yesterday I went out to start my car and all it did was make a clicking sound. So I push started it and drove around and my battery light came on. Is my alternator not charging the battery or is the battery bad? When I get the car started it stays running but once I shut it off and try to start it again it just clicks.
 
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The battery light coming on indicates the regulator noting that the alt is not charging. But as mentioned, just have the alt bench tested, along with the battery if you desire.

For home testing, comparing alternator output (at the alt charge cable stud) to battery voltage can be helpful.

Good luck.
 
That's exactly what happened to me when my starter went out. Battery was good and alternator tested good as well. The starter crapped out big time.

Thank God I had a friend with me who knew about the rolling start trick. I couldn't believe it worked, but it got me back to my house. I removed the starter and took it to Autozone for a free test. Put a new starter on and came back to Autozone and had the battery and alternator tested. I think I replaced those within a few weeks.
 
When my alternator went out (the car died in my driveway), after I tried to restart it, all it would do was click. After we jump started it, it would charge at 14 volts for a little bit, then drop to 12 then keep dropping.
 
The easiest test is to see if you are getting 13.2V or higher at the battery with the car running. If it is, then your alternator might be ok. Next put a DC amp clamp on the heavy duty gauge wire coming off of the alternator and see how many amps it's putting out.

If the alternator is putting current to the battery, then you need to charge the battery with a stand-alone charger and do a hydrometer or load tester.

Have you checked the water level in the battery???
Scott
 
The_Mustang said:
If the alternator puts out any kind of charge at all the light inside will extingish. I'm betting the alt is bad.

The light illuminates from too low or too high voltage. I also believe there is an ammeter that needs to see current as well. So you should be right. But I wouldn't make any assumptions until the system is properly tested.

I have seen that light illuminate on a ford chassis even when the alternator is charging.
Scott
 
The light is what turns the alternator on in the first place, no light no alt. There is a 12 volt current flowing to the light, then from the other side of the light to the Alternator. While the regulator is in "off" mode, the circuit on the regulator side is a ground, so the light is "on". however, when the alternator is excited when the car is turned on, the other side of the circuit is energized with voltage from the regulator when the alternator is working, this in turn creates current on BOTH sides of the bulb. We all know that one side of a bulb MUST have power and the other side MUST have ground to function. With power on both sides of the bulb it goes out.

Conclusion, the alternator MUST be working if the light is out and it MUST not be working if the light is on, plain and simple. The regulator simply will not function withought the 8 volt signal coming from that dash light.