# battery voltage?



## JWishnok (Dec 15, 2012)

When I first got my cruze it was at 15 and I checked it today and its down to 
12. I wouldn't suppose it would have to do with colder weather would it?


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## 70AARCUDA (Nov 14, 2010)

15Vdc is TOO *high*, unless you measured while the alternator was "charging" and conversely 12Vdc is _somewhat_ *low* (normal lead-acid car battery is 12.6Vdc).

If the car has been sitting for awhile, all the "ancillary" loads (security) CAN slowly drain down the battery...to a point...at which the car's computer will put everything into "power-down" load so that the battery doesn't get too low to start the engine...at least that's the way that GM claims it works.


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## Greasemonkey2012 (Jul 8, 2012)

that's normal man 



JWishnok said:


> When I first got my cruze it was at 15 and I checked it today and its down to
> 12. I wouldn't suppose it would have to do with colder weather would it?


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## kylevh21 (Mar 3, 2012)




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## 70AARCUDA (Nov 14, 2010)

...and, here's an earlier posting that describes how that GM Voltage Regulator Control (VRC) system works (5th post down):

http://www.cruzetalk.com/forum/17-o...uze-regulates-voltage-boost-fuel-economy.html


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## Bohdan (Apr 28, 2012)

My 2012 varies between 14.6 to 12.4 as it needs to.


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## Greasemonkey2012 (Jul 8, 2012)

Mine goes to 15.20 


Sent from my iPhone using AutoGuide.com App


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## MD5335 (Oct 16, 2012)

kylevh21 said:


>


A few years ago, I had a GM rental car (Caddy) with a voltmeter and, on a long highway trip, I noticed (because I was constantly playing with the DIC) it had dropped to 12.5 volts or so. I expected to be in a disabled rental car fairly soon...then I observed the digital voltmeter climb back up to 14 + volts after a while. So I asked my friend, who was a mechanic at a GMC dealer (and is now a mechanic at a Chevy dealer) what was up. His explanation was #3 above but he put it another, less romantic way, saying that GM wanted to give customers decent battery life and they could have either supplied better batteries or stopped cooking cheaper batteries by charging them more conservatively. They selected the reduced voltage route...makes sense to me.

My ECO does the same thing, varying between 12.5 or so and mid 14's.


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## sciphi (Aug 26, 2011)

Greasemonkey2012 said:


> Mine goes to 15.20
> 
> 
> Sent from my iPhone using AutoGuide.com App


Normal on a cold start when it's recharging the battery. If it doesn't drop back down to the mid-14's after a minute, something's wrong.


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