# Could you post your battery voltage info please.



## Cruz15 (Mar 17, 2016)

Could you post your battery voltage info please.
I had my battery replaced a few days ago, went and fueled up and checked what it was sitting at, it was at 11.8v brand new battery after two 1 hour runs today and sitting for 5 mins.
I have been using the car every day driving it at least a 1/2 hour drive one way. 
Voltage before start, length of avg drive and voltage after drive with a 5 - 10 min wait.
Thank you.


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## mkohan (Dec 19, 2015)

I have a 15 CTD with original battery. Put into service 11/15. 59K miles. volts generally read between 14-15 for my city 5 mile city commute. When on the highway for extended time, then volts drop to around 12. I generally don't look at voltage before start


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## obermd (Mar 3, 2012)

11.8 is correct prior to starting the car. This is actually the "12" volts for a 12 volt car battery. Full charging is 14.6 to 15.2 volts. Voltage ranges in between indicate lower levels of charging and are load dependent.


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## Rivergoer (Mar 30, 2017)

Cruz15 said:


> Could you post your battery voltage info please.
> I had my battery replaced a few days ago, went and fueled up and checked what it was sitting at, it was at 11.8v brand new battery after two 1 hour runs today and sitting for 5 mins.
> I have been using the car every day driving it at least a 1/2 hour drive one way.
> Voltage before start, length of avg drive and voltage after drive with a 5 - 10 min wait.
> Thank you.


Are you asking for the voltage directly measured with a voltmeter on the battery terminals? 

Or does the voltage reading on the DIC = the same thing?


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## KenH (Aug 27, 2017)

Five hours sitting in a semi-heated garage, 63°, then with ignition on no start… 11.9v
Backing out, lights, heater, radio on, 15.1v, then for about one minute.
Normal operating range while driving, 14.7 - 14.9v, after about three minutes.
2014 LT 1.4, with original battery.
Temps outside, 3° F


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## jblackburn (Apr 14, 2012)

"Full" voltage for a 12V car battery is ~12.5-12.8V depending on outside temp.

Mine's sitting at 12.4 before starting, outside in the teens. I had to put it on a charger last week because it was @ 11.7 and starting quite slowly. It took on about 3 hours of charge before.


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## snowwy66 (Nov 5, 2017)

obermd said:


> 11.8 is correct prior to starting the car. This is actually the "12" volts for a 12 volt car battery. Full charging is 14.6 to 15.2 volts. Voltage ranges in between indicate lower levels of charging and are load dependent.


11.8 is too low. My new battery clocks in at 12.2 - 12.3. 

Old one clocked at 11.9 - 12.0 and got warranteed for replacement.


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## snowwy66 (Nov 5, 2017)

If you're going off teh DIC. You can't do that. It's not real time live information. 

jblackburn posts the correct information. But you need an actual volt meter connected to the battery or run an obd2 app for the next best thing. The DIC isn't accurate. 

I just went the rounds with old and new battery. And was also concerned about the alternator. Turns out my concerns were unjustified.


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## chevrasaki (May 1, 2015)

Cruz15 said:


> Could you post your battery voltage info please.
> I had my battery replaced a few days ago, went and fueled up and checked what it was sitting at, it was at 11.8v brand new battery after two 1 hour runs today and sitting for 5 mins.
> I have been using the car every day driving it at least a 1/2 hour drive one way.
> Voltage before start, length of avg drive and voltage after drive with a 5 - 10 min wait.
> Thank you.


The best advice I ever got was to never have the battery voltage screen displayed on the DIC. Just look at anything else.


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## Patman (May 7, 2011)

I have a 4 year old battery in my 2013 RS and never look at it. Been @ 0 for the last several days and no problem so far. I just say does the car start? Maybe I am just simple minded and don't think about gauges like that unless there is a problem.


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## snowwy66 (Nov 5, 2017)

Considering all the electronics of our cars these days. And the fact that a low battery will effect the rest of the car. As in poor heating with vents, seats, and rear window. And anything else. 

That be the first clue there's a problem. As I've already found out. I"m one who likes to keep on top and fix problems before there's a problem. 

I wouldn't rely on the DIC for anything accurate. Not only is voltage unreliable. Fuel mileage is also off base. I do the math between mileage gone and gallons filled up. It's always short of what DIC says.


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## Cruz15 (Mar 17, 2016)

Rivergoer said:


> Are you asking for the voltage directly measured with a voltmeter on the battery terminals?
> 
> Or does the voltage reading on the DIC = the same thing?


The DIC. Thanks.


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## Cruz15 (Mar 17, 2016)

snowwy66 said:


> If you're going off teh DIC. You can't do that. It's not real time live information.
> 
> jblackburn posts the correct information. But you need an actual volt meter connected to the battery or run an obd2 app for the next best thing. The DIC isn't accurate.
> 
> I just went the rounds with old and new battery. And was also concerned about the alternator. Turns out my concerns were unjustified.


I will check with my obd2 to make sure its accurate.


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## Cruz15 (Mar 17, 2016)

So I checked my DIC compared to my OBD2 and they are in sync with each other, My DIC at least is very accurate.

So after driving around for an hour this morning then waited awhile before checking what the battery was at it was sitting at 12.2.

I just dont get why the battery was at 11.8 yesterday when it was driving for a longer period.
Why dosnt GM want the battery to charge up properly.
The fuel mileage was wonky, shifting was odd and radio was loosing stations yesterday as well.


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## Patman (May 7, 2011)

This morning after driving @ 1 mile, mine was at 14.7 as per the DIC and being in a garage over night


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## Rivergoer (Mar 30, 2017)

2014 CTD 80k Miles
New Battery (Oct)
Ambient Temp 60 F
20-minute Trip 60% Hwy
Voltage At Idle 
DIC - 12.4v 
SGII - 11.6v-12.1v

While driving SGII voltage varies from 11.6 up to 14.7


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## justin13703 (May 2, 2016)

obermd said:


> 11.8 is correct prior to starting the car. This is actually the "12" volts for a 12 volt car battery. Full charging is 14.6 to 15.2 volts. Voltage ranges in between indicate lower levels of charging and are load dependent.


A fully charged 12 volt battery is 12.6 volts. Each cell is 2.1 volts. But yes you’re correct about your range during charging.


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## snowwy66 (Nov 5, 2017)

Cruz15 said:


> So I checked my DIC compared to my OBD2 and they are in sync with each other, My DIC at least is very accurate.
> 
> So after driving around for an hour this morning then waited awhile before checking what the battery was at it was sitting at 12.2.
> 
> ...


So what you're saying is that your DIC isn't sluggish upon startup????? As in slowly builds the number up. What you're saying is that your DIC IMMEDIATELY showed 14+ volts upon startup? And matches your obd2 number for number the second that engine fires up?


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## Cruz15 (Mar 17, 2016)

snowwy66 said:


> So what you're saying is that your DIC isn't sluggish upon startup????? As in slowly builds the number up. What you're saying is that your DIC IMMEDIATELY showed 14+ volts upon startup? And matches your obd2 number for number the second that engine fires up?


My DIC is showing what my OBD2 shows, simple as that.


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## snowwy66 (Nov 5, 2017)

Cruz15 said:


> My DIC is showing what my OBD2 shows, simple as that.


My DIC DOESN'T.


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## dougc905 (May 24, 2015)

So to get back on track...

My battery died recently and I had to drive while nursing it for a week or so before I could get the new one installed. While nursing the original battery, I was looking at the dic frequently. Upon starting, the voltage read low, in the 12v range. After driving just a short distance, the voltage would climb into the 14v range. Then, once I was underway at city street speed, the voltage would again climb to show 15.3 - 15.4 values. I attributed this to the electronics calling for a hard charge on the bad battery.

Then I changed the battery for a new northstar battery. The voltage characteristics on the dic didn’t change! Same behaviour as before. The car starts and runs fine btw.

I went on two freeway trips in this period with the voltage staying in the 15.3v - 15.4v value range.

This morning I called the dealership and asked about it. The service advisor said that it was probably temperature dependant. Since it is so incredibly cold around here lately, the electronics are causing the battery to be charged constantly. He said to wait until the temp rises up to near freezing and then see if the voltage changes back to normal. He thinks it will. Supposedly the temp will be rising at the beginning of next week so I shall see.

Incidentally, forum member *nickd* had stated this temperature dependency in a post way back in 2012 or 2013. I found that post yesterday.


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## snowwy66 (Nov 5, 2017)

dougc905 said:


> So to get back on track...
> 
> My battery died recently and I had to drive while nursing it for a week or so before I could get the new one installed. While nursing the original battery, I was looking at the dic frequently. Upon starting, the voltage read low, in the 12v range. After driving just a short distance, the voltage would climb into the 14v range. Then, once I was underway at city street speed, the voltage would again climb to show 15.3 - 15.4 values. I attributed this to the electronics calling for a hard charge on the bad battery.
> 
> ...


T

The dic is slow at startup. And apparently has a seperate stream from obd2. 

Try using a obd2 app for a more accurate reading. I have a video of comparing the 2 readings but i don't see any way to post it to this websight. You can buy a bluetooth obd2 plug from amazon really cheap. I have an EML327 I also have a BAFX. I like the bafx better as the elm doesn't always connect. Torque app on your phone is free.


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## dougc905 (May 24, 2015)

snowwy66 said:


> T
> 
> The dic is slow at startup. And apparently has a seperate stream from obd2.


The dic is fast enough for the intended purpose. You’re supposed to be looking at the road, not a gauge or phone.


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## KenH (Aug 27, 2017)

Little to no difference compared to the DIC or OBDII.


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## snowwy66 (Nov 5, 2017)

dougc905 said:


> The dic is fast enough for the intended purpose. You’re supposed to be looking at the road, not a gauge or phone.


The car is parked. SMH. 

At startup there's a big difference. At running it's a slight difference. 

Fuel average is also off. Math on fill up always comes in around 3 miles lower then what dic says.

DIC will give a rought idea but obd2 is more accurate. And i like accuracy. I thought there was a problem with my alternator when i went off dic. But then i plugged in obd2 and realized that dic is the problem and not the alternator.


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## justin13703 (May 2, 2016)

Snowwwy66, the dic isn’t “sluggish” at startup as far as showing the battery voltage. That slow ramp up in voltage that you see after starting, is the charging system slowly ramping the voltage up after the vehicle is started. Anytime I’m using a obd2 reader the voltage is identical to what the dic says.

Also, when I figure up my real mileage against what the dic says, they’re both within a few tenths of 1 mpg from each other.


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## cruze-zeeke (Nov 1, 2013)

at start up my voltage is as low as 12.7 but when driving it hover around 15.2 to 15.3


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## snowwy66 (Nov 5, 2017)

justin13703 said:


> Snowwwy66, the dic isn’t “sluggish” at startup as far as showing the battery voltage. That slow ramp up in voltage that you see after starting, is the charging system slowly ramping the voltage up after the vehicle is started. Anytime I’m using a obd2 reader the voltage is identical to what the dic says.
> 
> Also, when I figure up my real mileage against what the dic says, they’re both within a few tenths of 1 mpg from each other.


The dic is sluggish. Obd2 shows immediate. Trip shows 36. Miles divide by gallons filled comes to 33. 

If there was a way to post the video. You all would see what I'm talking about on the alternator.


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## snowwy66 (Nov 5, 2017)

cruze-zeeke said:


> at start up my voltage is as low as 12.7 but when driving it hover around 15.2 to 15.3



Mine drops to 12.0 on average. Hovers around 14.5 to 14.0


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## snowwy66 (Nov 5, 2017)

HERE YOU GUYS GO. Watch the video. It clearly shows SLOWer dic buildup.

https://youtu.be/kxe3xmZEcP4


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## dougc905 (May 24, 2015)

In other news.... now that the outside temp is a bit warmer - around freezing today, my voltage is back to “normal” levels. Going slowly or idling at a light, it drops into the 12v range. Upon proceeding at city street speeds, it rises into the 14v range. So the outside air temperature affects the charging voltage.


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## Taxman (Aug 10, 2017)

Back in the day of 'voltage regulators', the good ones were temperature compensated, ran a higher voltage in cold weather. 

The first computer controlled alternator I had (1989 Plymouth) did the same. 

I suspect our Cruzes run whatever volts are needed to produce the desired charging amps, which would mean higher volts into cold batteries. 

When I charge my stored batteries, and they're really cold, I have to set my automatic charger to "manual" because otherwise it'll raise the battery (even a big group 49) to 14.5 volts in seconds and then shut itself off.
Last weekend was an extreme example of that, within a minute or so it'd be charging at 15.5V and less than two amps, when I knew the battery wasn't fully charged because it'd been running a computerized car for the past month.


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## Blasirl (Mar 31, 2015)

snowwy66 said:


> HERE YOU GUYS GO. Watch the video. It clearly shows SLOWer dic buildup.
> 
> https://youtu.be/kxe3xmZEcP4



I keep getting a "Video not available" message.


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## snowwy66 (Nov 5, 2017)

Blasirl said:


> I keep getting a "Video not available" message.


It's still pulling up for me. Says 4 people have viewed it. Computer and phone both pull it up. And it's marked for public viewing. 

https://youtu.be/kxe3xmZEcP4


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## Blasirl (Mar 31, 2015)

snowwy66 said:


> It's still pulling up for me. Says 4 people have viewed it. Computer and phone both pull it up. And it's marked for public viewing.
> 
> https://youtu.be/kxe3xmZEcP4



Comes up now, must have been a youtube issue.


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## 2015LT2 (Jan 20, 2017)

12.0 volts before starting car, chilly morning in North East.


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## Cruz15 (Mar 17, 2016)

Just an update. If I remote start it and let it idle till shut down it starts fine the next day in -20 but if I drive it for an hour mostly highway the next day it has a hard start. The only difference I can see is the dash lights and infotainment center stays unlit. Does anyone know of a power drain from those two items.
Thank you.


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## snowwy66 (Nov 5, 2017)

Cruz15 said:


> Just an update. If I remote start it and let it idle till shut down it starts fine the next day in -20 but if I drive it for an hour mostly highway the next day it has a hard start. The only difference I can see is the dash lights and infotainment center stays unlit. Does anyone know of a power drain from those two items.
> Thank you.


The only power drain SHOULD be the computers and radio. NOthing else.


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## Cruzator (Dec 31, 2014)

justin13703 said:


> Snowwwy66, the dic isn’t “sluggish” at startup as far as showing the battery voltage. That slow ramp up in voltage that you see after starting, is the charging system slowly ramping the voltage up after the vehicle is started. Anytime I’m using a obd2 reader the voltage is identical to what the dic says.
> 
> Also, when I figure up my real mileage against what the dic says, they’re both within a few tenths of 1 mpg from each other.


I wish my displayed vs calculated was that close. My calculated is typically 3 mpg higher than the dic shows. Dic also shows I've used more fuel, thus the lower mileage.


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## snowwy66 (Nov 5, 2017)

Cruzator said:


> I wish my displayed vs calculated was that close. My calculated is typically 3 mpg higher than the dic shows. Dic also shows I've used more fuel, thus the lower mileage.


My calculated is 3 lower. 

Haven't calculated lately now that mileage has gone down with winter blend.


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## Billy8098 (Oct 22, 2017)

Shortly after purchasing my car I noticed that the battery voltage on the DIC was lower than I was expecting, less than 13V. After doing a Google search I came across an article on a GM system called "Regulated Voltage Control", basically it reduces the voltage to ~12.8V under normal driving conditions in order to save an extra 1.5% fuel economy.


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## Cruz15 (Mar 17, 2016)

Billy8098 said:


> Shortly after purchasing my car I noticed that the battery voltage on the DIC was lower than I was expecting, less than 13V. After doing a Google search I came across an article on a GM system called "Regulated Voltage Control", basically it reduces the voltage to ~12.8V under normal driving conditions in order to save an extra 1.5% fuel economy.


Not sure why but my car does not do this ever. I have the voltage showing more than anything else. It is either really low 12.2 or 14.3 -14.4, it used to go as high as 15.6 under normal driving conditions. I have asked the dealers to check the alternator several times.


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## Cruzator (Dec 31, 2014)

Please see my post for a description of the charging system operation.

http://www.cruzetalk.com/forum/64-g...cussion/139089-battery-volts.html#post2077850

(There is probably a better way to link to this, but I'm not sure how).


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## Jondaytona (Apr 26, 2018)

Cruzator said:


> Please see my post for a description of the charging system operation.
> 
> https://www.cruzetalk.com/forum/64-...cussion/139089-battery-volts.html#post2077850
> 
> (There is probably a better way to link to this, but I'm not sure how).


Wow, another reason why I love this forum....Thanks! I'm an old school mechanic that's more into mechanical repairs than anything else, not to mention I've been working in a different field for the last 20yrs. Up til now, my charging system diagnostics have been "if it's under 13v it'll need an alternator if the battery checks out good". After getting this Cruze TD I've noticed this weird fluctuation in voltage as described and thought for sure something isn't right.

All this info makes sense with these newer computer controlled cars where everything is electronic, just didn't realize it. Thanks for helping me confirm and understand this.


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## snowwy66 (Nov 5, 2017)

Jondaytona said:


> Wow, another reason why I love this forum....Thanks! I'm an old school mechanic that's more into mechanical repairs than anything else, not to mention I've been working in a different field for the last 20yrs. Up til now, my charging system diagnostics have been "if it's under 13v it'll need an alternator if the battery checks out good". After getting this Cruze TD I've noticed this weird fluctuation in voltage as described and thought for sure something isn't right.
> 
> All this info makes sense with these newer computer controlled cars where everything is electronic, just didn't realize it. Thanks for helping me confirm and understand this.


I"m old school also. Retired 18 years ago. My aunt bought a 14 traverse. Uncle is also retired. Spent his whole life as a mechanic. We both thought the alternator was defective. First time I heard of gas saving alternators. 

What I can't figure out why. Chev needs that technology yet the imports don't. None that I've seen so far. 
Wonder if ford and chrysler do the same thing?


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## Taxman (Aug 10, 2017)

snowwy66 said:


> What I can't figure out why. Chev needs that technology yet the imports don't. None that I've seen so far.


First I heard about it was when I went to a Nissan forum trying to figure out why a friend's new 2013 Sentra kept refusing to start. He'd get somewhere early, listen to the radio or talk on the car's bluetooth for 15 minutes, and then the car would want a jump half an hour later when he tried to drive home. So I went for a drive with my scangauge, and sure enough, the voltage kept dropping to 11.8-12.2 when the alternator would turn off. 

It's slightly annoying that the car would deliberately run around with the battery half charged, but it's infuriating or potentially dangerous (depending on where/when it strands you) when the car refuses to engage the starter with the battery half charged.

Two years ago we put a bigger battery in it and he bought a jump pack. Since then it's started every time. He still calls me from the car when he has time to kill, so I guess the bigger battery helped with the no-start issue (or he's running the engine for air conditioning when he parks).


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## Jondaytona (Apr 26, 2018)

snowwy66 said:


> What I can't figure out why. Chev needs that technology yet the imports don't. None that I've seen so far.
> Wonder if ford and chrysler do the same thing?


It's cuz General Motors knows exactly what they are doing and far more superior than others! :th_SmlyROFL:


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