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Discussion Starter #1
Driving to work this AM, battery light just randomly came on? No trouble starting up, any suggestions what might of triggered the light to come on? Any help would be appreciated
 

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Im leaning towards alternator....could be a bad cell though. Go get it tested fro free at just about any autoparts.
 

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mroe then likely the alternator. made the mistake of changing the battery in my truck when the light came on then had the replace the alternator a day or two later.
 

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Discussion Starter #5
I just went to start it up again and no light, so I am having it tested right now. How much do prices range for new alternator?
 

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Last year my battery was going bad and the light came on. A couple months ago my alternator was going bad and no light. Only way to know for sure is to go get it tested. Watch your Volt gauge on your dash, if its pointing more towards the right then odds are its your battery going bad. If it starts moving toward the left then odds are its your alternator. This isn't a fool proof way, but is usually a goo indicator as to what's happening.

---------- Post added at 10:20 AM ---------- Previous post was at 10:19 AM ----------

I just went to start it up again and no light, so I am having it tested right now. How much do prices range for new alternator?
Shouldn't be more than $250 for a brand new one. Plus whatever core charge.
 

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sLbxO143 said:
I just went to start it up again and no light, so I am having it tested right now. How much do prices range for new alternator?
I just paid $130 + core for my f250 ,just to give you an idea.
 

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Discussion Starter #11
Thanks for the help guys. I jus got the car back they said everything looked fine and the voltage didn't fall below 10.5. The battery is only 1 year old and it didn't come back on, they said don't worry about it
 

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Discussion Starter #13
I'll see if it gets worst, they said everything was fine And car seems to be running fine & starts up fine so im going to wait it out for a little while.
 

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If you keep running it like that you'll ruin your battery. It's possible your regulator is going out and only charging intermittently, but something is wrong. However, if you keep depleting a non-deep cycle battery too low, it will damage the cells and you'll need a new one of those too. Also, bad batteries can kill alternators by overworking them.

It may not mean much, but I am ASE certified and have worked in automotive parts for 7 years, so I know a bit of what I'm talking about.
 

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I agree...im also ASE cert and 10v is a no no...11s would have me worried. Believe me i ruined my last battery by waiting to late to swap the alt.
 

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Discussion Starter #16
It is leaning more towards the H on the battery gauge. So what are you guys saying is wrong the battery or the alternator? They never said it was on 10.5 V they said it never fell below that so it would of been high and I am misunderstanding what they are saying. And the light hasn't been on since it flickered on and off once
 

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sLbxO143 said:
It is leaning more towards the H on the battery gauge. So what are you guys saying is wrong the battery or the alternator? They never said it was on 10.5 V they said it never fell below that so it would of been high and I am misunderstanding what they are saying. And the light hasn't been on since it flickered on and off once
That dummy gauge is pretty useless. Use the diagnostic mode on the odo and watch your actual voltage while driving
 

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If your battery is load testing to 10.5v, that's good. When the vehicle is off, 12.5v is the standard battery voltage. With the vehicle running you should be north of 13v, 13.5v is ideal.

At this point, my guess is either the voltage regulator in the alternator is going out intermittently or you have a loose/bad connection somewhere. You can test the latter by hooking a volt gauge to the battery while its running and wiggling the alternator wires and seeing if the alternator quits charging.

I hate phantom electrical bugs like these, just saying.
 

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sLbxO143 said:
How do I watch while I'm driving? And what is the voltage supposed to be at?
With the key off press and hold the trip reset. Turn the key to the on position while pressing until the gauges sweep. Start the car and press the trip reset to cycle through modes until you reach voltage. Glance occasionally to see if there are variations
 
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