# Chevy Cruze Battery voltage?



## 70AARCUDA (Nov 14, 2010)

...14.7 Vdc is the "normal" re-charging voltage for a mildly _dis_-charged lead-acid battery (warm weather)

...that 15.4 Vdc reading is slightly high and is a possible indication that the alternator & voltage regulator are attempting to "_*re*_-charge" the battery after a _large_ current load has been used, such as after a "cold" start. And, yes, voltage readings _above_ 15 Vdc are not usually good (can burn-out lamps), but will often occur during COLD weather.

...a "no-load" voltage below 12.6 Vdc points to a battery that's either weak or not fully charged.


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## elwood58 (Feb 2, 2011)

I just checked mine on the DIC and it reads 14.7v.


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## cerbomark (Dec 13, 2010)

the last time I checked I had a 15.1. I wouldn t worry about anything in these ranges.


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## jlalill (Nov 1, 2010)

cerbomark said:


> the last time I checked I had a 15.1. I wouldn t worry about anything in these ranges.


mine is now 15.1 also...so not to worry....


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## itsbmw (Feb 5, 2011)

Throw 1500watts RMS in your trunk and you won't be seeing that kind of voltage anymore, I was surprised these cars came with 120amp alts, but I'm happy, I won't be upgrading my alternator for my sound system.


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## 70AARCUDA (Nov 14, 2010)

...there's also a *140 Amp* alternator available, RPO: KG9 - Generator 140 A


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## jaygeo1 (Nov 10, 2010)

*Charging Voltage........moves..*

Around 2007 or so GM's charging system became more "intelligent" and monitors the battery and system _loads_ closely. The system will *vary* the charging voltage to balance the load and battery state of charge. I really noticed this more so on our 2009 Silverado ( with the big voltage gage ). At times I'll see the voltage down around *12 *volts (system broke!) or right up there around *14/<15 volts* ( ah..,that's better). So, don't be alarmed...it is *now* the *norm *to see this voltage fluctuation.


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## maddy (Jan 25, 2013)

Check the battery voltage when the battery is completely cool. it should be between 12v to 12.8v.


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## NickD (Dec 10, 2011)

Batteries have a negative temperature coefficient that also varies with the battery manufacturer due to chemical differences. Charging voltage depending on the battery and temperature can vary anywhere from 12.9 to 15.5 volts. 

The colder the temperature is, the higher the charging voltage as to be over a defined temperature range of -40 to 125*C.

If you applied 12.9 VDC to a battery at -40*C, would would not be charging it, would be discharging it instead. Worked closely with then the Delco battery division for setting up the desired temperature curve for the longest battery life. Since these curves change with aftermarket batteries, best to stick with the same battery your vehicle came with. 

What you are seeing in your changing charging voltage is not only perfectly normal, but intended.

One of biggest mistakes made was mounting the voltage regulator inside of the alternator that also contains that temperature sensor, fooled by the extreme heat of the alternator for undercharging the battery. Delco battery division was screaming about that as their warranties went way up. We did add an external sensor for the CS-144 sensor, but was only used in higher end GM vehicles, added about 20 cents to the cost.

Not a problem for Delco anymore, we are history. Prices of our vehicles are skyrocketing, everything inside is made cheaper/ Toyota, Honda, etc. are no better in at least this one respect. 

Don't blame engineers, we all know better, but had to comply or they would find somebody else.

Personally, I am happy to see 15.4V when the ambient temperature is -15*F.















v


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## Richard (Dec 1, 2012)

jlalill said:


> just checked my battery voltage...in a short drive..it's 15.4..
> 
> is this normal..i thought ranges should be below 15 or are ranges higher now...
> 
> ...


I checked mine the other day and it read the exact same voltage. 15.4 on the button. But battery voltage varies. 15.4 seemed a bit high to me, but that could be the characteristic of the Cruze. It was cold outside and the volts read higher in colder weather. Also, it does have a lot of electronics and it needs a lot of voltage to power them.


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## Mikeske (Jun 19, 2012)

My 1998 Buick Park Avenue shows on the DIC that the battery voltage is between 13.4-13.8 and never has shown higher. Out of curiosity one day I grabbed my Fluke meter and checked the voltage when the engine running on the battery, actual voltage on a calibrated meter was 14.6 and I checked the DIC at that time and it show 13.5. Remember that the gauge in the car can and often is inaccurate. My Cruze I did the same test and it was spot on with the Fluke meter. Automotive gauges and meters are and can off by a bit and not effect the car as the real readings can be a lot different. Just remember that the vendor that made the gauge or reader for the system has a certain range that are acceptable. 

I always think that the automotive industry taught the government about the lowest bid. John Glenn was asked what he was thinking strapped into the space ship on the first orbital flight and he said all that he think about was that the rocket and space ship were made by the lowest bid.


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## NickD (Dec 10, 2011)

For years, the automotive industry used an ammeter in series with the battery, with low output generators, would show a discharge with the headlamps on and at idle. The actual load taken from the generator was not shown, but would show a positive charge to the battery if it was low. Once the battery was fully charged, this ammeter would go to zero.

Sound confusing it was, so finally the ammeter was dumped in favor of just showing the alternator output voltage. An expanded scale voltmeter was adopted to use a cheaper smaller meter, but a voltmeter is nothing more than an ammeter with a series resistor. That resistor can be calibrated to read accurately.

And for that matter, so can the oil pressure and temperature gauge refering to strictly analog gauges. For years, GM and other were cheating with the oil pressure gauge, just using a fixed resistor to a low pressure switch for oil pressure. As long as that switch was closed at 2.5 psi, oil pressure would show full, under 2.5psi, switch would open of zero oil pressure. Not much different than using an oil pressure lamp. Cruze is using the same cheap scheme, one reason to judge actual engine oil pressure is to install an accurate gauge.

Fuel gauges are far more complicated, rare to find a linear tank in automotive like rectangular, the resistance of the sender has to match the characteristics of the tank. This could be done with nichrome with the spacing between the wires to match the characteristics of the tank, but now they are using a very cheap conductive ink on a ceramic substrate. Average cost to produce a resistor of this type is like 3/4 of a cent. Also subject to erosion caused by ethanol based fuels.

Yet another factor is that the sender has to be mounted in the precise center of the tank, if forward or sideways, vehicle level plays a role what that sender will output.

With the Cruze, compensation is made by a single multiplexed A to D converter, where digital data is mapped to a lookup table for mean corrections. But definitely more accurate than pure analog for both the fuel tank and voltage displays.

Speedometers is yet another gauge, with the analog cable driven type had to change the strength of the magnetic field of a permanent magnet. this was tricky for calibration. Linearity is also a factor. Cruze uses a Vss that applies pulses to the PCM. With trucks could actually calibrate these yourself with different tires. How this is done with the Cruze, have yet to find out. Mine is darn accurate compared to the GPS readout. But suspect as the tires wear, will read lower. Ironically, I can purchase a 15 buck bicycle speedometer where I can easily set it to one part in 10,000. But can't do that with my Cruze. Maybe my dealer can do that with the generation III, haven't learned that yet.


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## GoldenCruze (Dec 18, 2011)

Richard said:


> I checked mine the other day and it read the exact same voltage. 15.4 on the button. But battery voltage varies. 15.4 seemed a bit high to me, but that could be the characteristic of the Cruze. It was cold outside and the volts read higher in colder weather. Also, it does have a lot of electronics and it needs a lot of voltage to power them.


It is not the battery charge level that is being reported by the DIC. It is the charging system output that is being shown. That will vary according to the load put on it by the engine and everything else that uses electricity.


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## mjrCrash (Dec 7, 2017)

Excellent info !! thank you ,


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## Michelleb86 (Feb 21, 2020)

So its OK if the battery is 15.4v in like 15 degrees weather after it wouldn't start and was jumped. Seems the battery.would recharge but I don't drive it far.


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## eddiefromcali (Aug 21, 2017)

Normal


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## Blasirl (Mar 31, 2015)

How to Test Your Auto Battery | Battery Testing & Maintenance


/battery-testing-and-maintenance/car-battery-voltage-and-testing




www.autobatteries.com


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## gurroana (Aug 22, 2020)

my battery voltage is at 11.6 volts and my car won't start.


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## ChevyGuy (Dec 13, 2014)

gurroana said:


> my battery voltage is at 11.6 volts


There's your problem. 11.8 volts is considered "dead".


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## nayteez (7 mo ago)

so my car wouldn't start the other day so I charged the battery... I drive it the next day and my meter reads 12.4v at the accessory dc port. I turned on AC and it dropped to 11.9v... a week later of not driving, I check the battery at the terminals and I see 12.5v. I clean the terminals and hook the battery back up to the car and start it.... Now I'm seeing 15.2v on the accessory port and at the battery and it's 85 degrees F outside.... no warnings or error codes. Any thoughts or cause for concern? 

2016 Cruze LT RS-pkg Manual


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## snowwy66 (Nov 5, 2017)

15.5 is the new norm.


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## Johnny B (Jun 4, 2019)

nayteez said:


> Any thoughts or cause for concern?


Yup, seems like a clear case of needing a new battery.


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## Blasirl (Mar 31, 2015)

nayteez said:


> so my car wouldn't start the other day so I charged the battery... I drive it the next day and my meter reads 12.4v at the accessory dc port. I turned on AC and it dropped to 11.9v... a week later of not driving, I check the battery at the terminals and I see 12.5v. I clean the terminals and hook the battery back up to the car and start it.... Now I'm seeing 15.2v on the accessory port and at the battery and it's 85 degrees F outside.... no warnings or error codes. Any thoughts or cause for concern?
> 
> 2016 Cruze LT RS-pkg Manual


Service Bulletin - NHTSA SB-10057574-8899
SB-10089945-2280
*How-To: Installation of the Big 3 Cruze Kit*
Clean the Terminals
Cruze Battery Upgrade Options
Battery Tab
Both positive and negative _battery cables_ at the battery are torqued to *40 in-lbs*
The_ battery plate nuts_ are torqued to *106 in-lbs*
and the b_attery hold down_ arm is torqued to* 80 in-lbs*


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