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Discussion Starter #1
Hi, what does it mean when I test the battery with a multimeter and it shows 17 instead of like 12.6 or 13 or whatever it's supposed to show?
according to what I read, that means the alternator is overcharging the battery and that is of course bad. The car has been sitting for about 2 weeks but it started a few days ago and now it won't start. Those may not be related to the multimeter reading but I'm more concerned about the multimeter reading right now as I think, if I can get a mechanic to work on it, they'll be able to find out. Thanks in advance
 

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3s-gte in a Camry?!?
'89 Camry Alltrac
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The car has been sitting for two weeks and it read 17 volts at the battery? I'd suspect the multimeter is the problem (either how it is being used or the meter itself). Chemically, a 12V lead-acid battery won't keep 17 volts across the terminals after a (way to high) charging voltage is applied.

You might be able to read something just over 13V at the battery right after shutdown of the car, but likely it will be 12.7V or lower.

-Charlie
 

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If the battery reads 17V while the engine is running, according the internet the voltage regulator (IC regulator) in your alternator is bad. The highest it should read is 15V.
 

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Discussion Starter #4
The car has been sitting for two weeks and it read 17 volts at the battery? I'd suspect the multimeter is the problem (either how it is being used or the meter itself). Chemically, a 12V lead-acid battery won't keep 17 volts across the terminals after a (way to high) charging voltage is applied.

You might be able to read something just over 13V at the battery right after shutdown of the car, but likely it will be 12.7V or lower.

-Charlie
I turned the voltmeter on, and put it on 20 dcv, red lead in the middle hole, put the black lead on the black terminal and the red lead on the red terminal and that's what it says. About 17 plus a little something
 

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Discussion Starter #5
Update, I changed the battery in the voltmeter, check the battery in the car again and it reads 14.04. that makes more sense.
But I would expect it to be down because I tried starting it several times yesterday and it wouldn't start and it sounded like the battery was getting lower in charge. But I could be wrong . There's never been a time in the 10 years I've had this car when there was a problem other than electrical with the battery and the alternator where it wouldn't start. It might need gas for all I know it was low when I last drove it thinking that I was going to be able to find a mechanic within a couple of days and that didn't happen. I don't know what it is around here it's pretty darn lame
 

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1995 T100 2WD & 1993 MR2
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Where are you, maybe someone can recommend an Independent shop or mechanic close to you.
Will it start if you get it jumped so you can take it to a shop?
If it does, then maybe just go buy a new battery for it.
 

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3s-gte in a Camry?!?
'89 Camry Alltrac
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Update, I changed the battery in the voltmeter, check the battery in the car again and it reads 14.04. that makes more sense.
14V is a reasonable reading when the engine is running, but the battery chemistry physically will not allow 14V across the terminals if there is no outside source of electrical energy... So, closer but no cigar yet. Hmmm.

-Charlie
 
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