Dead 12V battery in 2019 Niro EV

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About a month ago, I went out to find my e-Niro 12V battery dead. Called KIA roadside assistance to help get it started and I drove it to the dealer. They, of course, could find nothing amiss and had no suggestions.
I immediately ordered a Li-ion starting battery, as well as a trickle charger, just in case.
Anyway, one night I noticed that the right-hand green charging light (right-hand when viewing through the windshield) was blinking. I never had seen that.
I checked the manual and it states that it blinks when charging the 12V battery. The lamp was out the next time I looked.
The car was just sitting, not charging at the time.
Interesting. Hope this helps. Although, it would be nice to know the conditions that this happens in.

There is a setting that will charge the 12 volt battery when the car is not on or plugged in. When the green light is flashing that is what is happening, you can set it to not charge the 12 volt battery in that manner.
 
That's very interesting. Thanks.
I don't remember changing any settings and I would sure like to know where to find it. That way I can ensure the it stays the way it is and not mess with it.
If you could let me know what that setting is and where to find it I would sure appreciate it.
Thanks again.
 
There is a setting that will charge the 12 volt battery when the car is not on or plugged in. When the green light is flashing that is what is happening, you can set it to not charge the 12 volt battery in that manner.

I'm not aware of such a setting in our 19 e-Niro. There is also no utility setting (that I can find) commonly used by Bjorn in his videos. Different software package or model year?
 
In the manual for my 2020 US Niro EV EX Premium there is a feature called 12 V Aux. Battery Saver+. It's on page 1-52.


Okay, found it in the cluster settings. It was checked on, but still allows the 12 Volt battery to drain while the vehicle is ON and plugged in (in my case) and verified with a simple cigarette voltmeter. The software will allow the 12 Volt battery to die while the vehicle is ON, plugged in, with significant charge in the HV battery. Unplugging the vehicle after turning the vehicle ON will have no change on the 12V discharge (will not charge 12 V).

The only exception to 12V battery discharge, while plugged in, is during active charging (ie: the HV battery hasn't reached its user set max charge AND within scheduled charge times, if selected). Otherwise, the vehicle will actively discharge the 12 Volt battery while hooked up to the grid and with excess energy stored in the HV battery.
 

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I'm not aware of such a setting in our 19 e-Niro. There is also no utility setting (that I can find) commonly used by Bjorn in his videos. Different software package or model year?
To access utility mode. The car must be turned on to the run position. Green arrows on the dash. On the steering wheel settings scroll down to convenience, second choice down is utility mode. This only appears when the car is turned on to run.
HTH
 
I guess I fell comfortable with GM's approach. I can't imagine a scenario where GM's software would allow the 12 V battery to die with energy available in the HV battery under normal conditions. Plugged in or unplugged, and with accessory mode or ignition on, the DC-DC converter will keep the vehicle operating, and charged, in the Volt.

I'd imagine Tesla's approach is similar to GM's, as I haven't heard of this scenario over yonder.

Let me help you. I owned a 2017 Chevrolet Bolt EV for two years. I parked in my garage one evening. I didn't plug in because it still had 160 miles of range. The next day, I went out to get in it, and it was totally dead. Later that day, when I had time, I ascertained the the 12V battery was dead. I jumped it according to the instructions in the Owners' Manual with a power pack. That woke it up so I could charge the car. It was fully charged after about 15 hours, but I left it on charge for another day. Then, I tried to drive it. Although I could turn the car on, I couldn't shift into reverse or drive, only into neural or park. It was towed to the dealer. The dealer claimed that the 12V battery was dead when they received it. They couldn't explain why it was dead, and adamantly insisted that there was nothing wrong with the battery or the car. Therefore, it must be normal for Bolt EVs to become undrinveable for no reason.
 
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To access utility mode. The car must be turned on to the run position. Green arrows on the dash. On the steering wheel settings scroll down to convenience, second choice down is utility mode. This only appears when the car is turned on to run.
HTH

Excellent, yes. I figured that out last night after going through a bunch of hypothetical scenarios on the vehicle (plugged in, on, accessory etc). Also ended up downloading the PDF operator manual after a brief search in the glove box, just to recall the dealership never offered one to begin with (probably accidentally removed at delivery). Thanks!

Unfortunately, I still cannot get the 12 Volt battery to charge while plugged in and ON. I used 120 and 240V, Vehicle ON, or accessory ON....the vehicle will refuse to draw from the grid, while actively draining the 12 Volt.
 
Let me help you. I owned a 2017 Chevrolet Bolt EV for two years. I parked in my garage one evening. I didn't plug in because it still had 160 miles of range. The next day, I went out to get in it, and it was totally dead. Later that day, when I had time, I ascertained the the 12V battery was dead. I jumped it according to the instructions in the Owners' Manual with a power pack. That woke it up so I could charge the car. It was fully charged after about 15 hours, but I left it on charge for another day. Then, I tried to drive it. Although I could turn the car on, I couldn't shift into reverse or drive, only into neural or park. It was towed to the dealer. The dealer claimed that the 12V battery was dead when they received it. They couldn't explain why it was dead, and adamantly insisted that there was nothing wrong with the battery or the car. Therefore, it must be normal for Bolt EVs to become undrinveable for no reason.

I'm more referencing when the vehicle is ON or in accessory mode (both plugged in or unplugging after turning vehicle on while plugged in). At least that's the issue I'm having with the e-Niro. I can mistakenly configure the e-Niro to actively drain the 12 V battery with the vehicle operating (ON) in accessory or ON while plugged in. This scenario only happens when I attempt to draw power from the grid (turn power ON while plugged in). The 12 Volt battery light will automatically illuminate, and I cannot find a sequence or configuration where the 12 Volt battery won't drain with the vehicle powered up, and plugged in.

GM, or at least the Volt, doesn't allow for this loophole when the vehicle is plugged in and ON, or in accessory mode.

(Not using the remote UVO app, but manually pushing start)
 
I recently drained my 12V battery at the drive in movie. I know I had the car in the on position at the start, but I guess I must have accidentally turned it to auxiliary at some point. A couple of people offered to jump but then got scared off by the fact that it was an EV, so we called roadside assistance who were able to get it started.

In the future, aside from not letting it drain in the first place -- I only learned about the "utility mode" after this happened -- does anyone have any advice on what to do if this happens again? I've read that the PHEV has a "battery reset button" but can't see anything about this in the EV manual. I know there's a a "aux battery saver mode" but I've read that it doesn't do a lot. Is one of these USB power pack jump starter things enough to get a Niro through the start sequence so I can turn the vehicle on and get it running off of the big battery? And, finally, how is this even a thing in a car that's basically a giant rolling battery?
I've been having the dead battery problem for 3 months. Took it to the dealer twice and neither time could they figure out what was wrong. Last night I think I discovered the issue. If I turn the headlights off before turning off the motor, the battery is fine the next day. But yesterday I left the headlights in AUTO position and 20 minutes later the 12v battery was dead.
 
That certainly defeats the purpose of the auto-headlights, doesn't it?
Knock on wood, I've not had that issue. Although, I have had a dead 12v once, for unknown reasons. None since the dealer decreed that all was well. But, that issue is now stuck in the back of my mind.
I'm still trying to imagine why they don't use the traction battery for the 12v system. The only explanation that is ever given is that it would be expensive to convert all of the 12v items. BUT, the car already does DC/DC conversion to charge the 12v battery. Why not just use that converter to run the 12v items?
 
That certainly defeats the purpose of the auto-headlights, doesn't it?
Knock on wood, I've not had that issue. Although, I have had a dead 12v once, for unknown reasons. None since the dealer decreed that all was well. But, that issue is now stuck in the back of my mind.
I'm still trying to imagine why they don't use the traction battery for the 12v system. The only explanation that is ever given is that it would be expensive to convert all of the 12v items. BUT, the car already does DC/DC conversion to charge the 12v battery. Why not just use that converter to run the 12v items?
For the Niro, at least, the EV version was built from the bones of the Hybrid and ICE versions, so it was easy to use the 12V circuitry and battery. I suspect that going forward, EVs will dispense with the 12v battery. I also have a Tesla Model Y and it does not have a 12V battery. (actually, I think it does, but it is not visible. I did read that Musk is going to use Lithium 12v batteries going forward)
 
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I thought I remembered that the Model Y was going that route. It is good to hear that it can be done. Thanks!
Actually, I had heard that it doesn't have one and I certainly can't see it anywhere, but I am now reading that it does have a 12vbattery, but it may be Lithium Ion.
 
Since I replaced my 12V battery after it failed on me, my car has had no more battery related issues since. That is both good and yet actually quite confusing. I did put in a somewhat larger capacity 12V when I swapped it out.
Can you tell me what replacement battery you purchased?
 
Can you tell me what replacement battery you purchased?

If I think of it I'll take a picture when I can. It's same width but a bit deeper in dimension. Same height. Purchased at Wal-Mart because they are impossible to beat on car batteries.
 
If I think of it I'll take a picture when I can. It's same width but a bit deeper in dimension. Same height. Purchased at Wal-Mart because they are impossible to beat on car batteries.
Thanks!

I actually went into Autozone and saw that battery group size 67 fits perfectly! It even has the port for the tube (i think).
Duralast Gold Battery 67R-DLG Group Size 67R 400 CCA
 
I noticed my green dashboard LED blinking when the car was not hooked up to the charger a few days ago.

I also had an unsettling moment where the motor would not engage (though it claimed I was already in gear when I worked the shifter-dial thing. Car would not move though). The charging system indicator light for the 12V would not turn off. I cycled power a couple of times with the same result. Around the 3rd of 4th cycle it started normally.

This is 20k miles into the life of the 2019 vehicle in a mild climate (SF Bay Area) and and I have not been changing any settings in many months. Could the 12V battery be approaching end of life less than years after it was factory installed? (June 2019 build date according to the VIN)
 
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