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Discussion Starter #1
I can jump it and start it, but as soon as I shut it off, it's dead. The Volt didn't come with the charger so the hybrid battery is at 0%, but would the 12 volt battery be bad if I had no lights, etc?

I got it on a trickle charger right now (12v). Has a Delco battery in it so I am assuming it the original battery.

Just curious how these Volts are powered.

Much Thanks,
Leo
 

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Your trickle charger (or other for that matter) should be one that is smart to handle the requirements of a an AGM or you could wreck the battery. If you don't have a charger to charge main battery you can run it in Mountain Mode and the ICE will charge the main battery as it runs (up to 40%), not efficient (compared to wall charging) but will give you some EV running till you get your charger up and running. With main battery with some juice in it, it will charge the 12V battery when car is on.
 

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The car needs the 12V battery to start operating from the traction battery.

You need a new 12V battery. If it's really the original battery (>5 years), it's had a good life.

Here in Phoenix AZ, we're lucky if a battery lasts 3 years (conventional ICE vehicle, exposes battery to engine heat on top of summer heat).

Volt 12V batteries have a cushy life - kept away from engine heat/vibration, and not asked to provide large cranking current.
 

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The main EV battery is never at true 0%. It always has a reserve even if you never charge it with an EVSE. The gas engine turns off at stoplights, right?

The 12v battery is toast. Replace it.
 

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That should not happen unless the 12V battery is dead or there is a bad connection to the 12V battery. The battery might be dead from age/abuse, or it may not be receiving a charge for some reason. Start by checking that all battery cable connections are secure at both ends, and also test the battery voltage.

This has nothing to do with your charging cable that you plug into the wall. That is not needed for the car to work properly. Also look under the trunk floor for your charging cable. It may be hiding there.

These AGM batteries are pricy, so shop around for a good deal. Sam's Club has a good price ($130).

Trickle charging the battery may solve your problem temporarily, but whatever the real cause is will still be there.
 

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Sounds like a classic failed 12V battery. If it hasn't been changed, this is about the right timeframe for it to be likely to fail, too.
 

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Discussion Starter #7
Your trickle charger (or other for that matter) should be one that is smart to handle the requirements of a an AGM or you could wreck the battery. If you don't have a charger to charge main battery you can run it in Mountain Mode and the ICE will charge the main battery as it runs (up to 40%), not efficient (compared to wall charging) but will give you some EV running till you get your charger up and running. With main battery with some juice in it, it will charge the 12V battery when car is on.
Yes, my charger is a batteryminder and has the agm function. Going to see if it made a difference this morning. Either way, I have no history on the battery so picking up a new AGM today to replace it. Hopefully this cures it.
 

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Thanks guys for all the great replies. I agree, battery is getting replaced today. Will report back after I install it.
 

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Just curious how these Volts are powered.
Just as background, because it will probably matter sometime...

12v powers the car when it's "off". The high voltage (HV) battery output is completely disconnected. You need that 12v power to handle starting the car, or to start charging the HV pack from the wall. In the 2013 (I'm pretty sure), the wall charging does not charge the 12v -- it only charges when the car is on.

Starting the car requires several seconds of very even power from the 12v, to start up many computers in the proper sequence. The startup sequence is quite sensitive to power fluctuations, so a weak battery will cause mysterious gremlins that look like things broken but are just "didn't get enough 12v power at the right time". Replacing the 12v fixes a lot of weird things, especially ones that don't repeat from day to day. Once all the computers are started up and working properly, then the contactors for the HV pack close and power feeds to the Aux Power Module (APM -- the Volt's "alternator"). The APM will take over powering the low-voltage parts (fans, lights, computers, pumps, etc) and first check, then start charging the 12v battery. That battery check before charging is because reviving actually dead AGM batteries is very tricky, and prone to going wrong in Very Bad ways. If the 12v is too dead, the APM will not charge it.

The 12v does not start the engine. The engine is started by the secondary motor/generator (MGA) turning the engine to get fluids flowing, then spark is applied. You have a 55kw starter motor. The engine WILL START if it's able to run at all.

Since the 12v doesn't start the engine, and the car-starting sequence is so sensitive to power problems, it's often difficult to tell when the battery needs replacing. Unlike regular cars, the Volt's manner of using the 12v means hot climates (like San Diego, Arizona, New Mexico, Texas) tend to be much harder on batteries than cool ones. It's not unusual for a Volt AGM to need replacement in four years in a hot place, and other Volts tend to need replacement 12V batteries in 6-7 years. (Exceptions either way happen, but a LOT of people with early Volts have had to replace theirs.)
 

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Discussion Starter #11
Thanks for the great responses. Picked up my new AGM from NAPA and it worked like a charm. Everything works like it should and she fired right up. Now to source a charger.

Thanks so much for all the assistance!!

Leo
 

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"If the 12v is too dead, the APM will not charge it. "

thanks for that note - I wondered about that.

We should also say if the APM does decide to charge the 12 Bolt battery it has 100+ amps at its command
so if trying to re-activate a 12 volt battery that may still function you do not need a long time on an external charger.

a low cost clamp on amp meter helps.
 

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Just as background, because it will probably matter sometime...

12v powers the car when it's "off". The high voltage (HV) battery output is completely disconnected. You need that 12v power to handle starting the car, or to start charging the HV pack from the wall. In the 2013 (I'm pretty sure), the wall charging does not charge the 12v -- it only charges when the car is on.
I believe all generation 1 cars have a secondary charger in the HV charger module that provides 12V power during charging and would charge the 12V during that period. Of course, you needed 12V power on the car to initiate the charge session, so this won't matter unless you have a working 12V battery (or jump the car.)
 

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I believe all generation 1 cars have a secondary charger in the HV charger module that provides 12V power during charging and would charge the 12V during that period. Of course, you needed 12V power on the car to initiate the charge session, so this won't matter unless you have a working 12V battery (or jump the car.)
Oh that's right... Thanks.

The thing I was thinking of is that the charging for the 12v on the (early) Gen 1 cars never resumes. If there's a draw or a sag due to surface charge/age, then an old AGM battery could be "charged" but not long stay strong enough to actually get the car turned on properly. Newer cars that check the state of the 12v while plugged in can mask the aging of the 12v even longer by frequently topping up during plugged-in idle weeks, but the first week in an airport parking lot in a year may strand someone.
 
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