12V battery

Well I was greeted to another dead 12v battery this morning before heading off to work. Was driving it in my daily and normal commute of around 60km day until I parked it last night. It's been regularly daily driven. Was around -5C overnight. No unusual accessory use, wasn't plugged into EVSE, it's drain appears completely random. I don't get it?

Sent from my SM-G955W using Inside EVs mobile app

 

Well, that EVSE was supplied with the car so it all must work together. I think the graphs clearly show that there is a problem. At least you're in a part of the world where EVs are common, so they should have excellent resources at their disposal.

The OBD comms wake up the moment charging starts. The current shunt only sees current at the aux battery so it doesn't matter what other 12V loads are present, noting on my graph that current reaches zero while still at charging voltage. The scaling is roughly verified because my calculation shows that the total energy input matches the expected loss due to quiescent current drain.

You should get a BM2, it provides the peace of mind of being able to track the voltage change day to day. You just have to catch a fatal voltage drop before the device loses its memory.

 

If you want to do that, a good time to check is an hour or two past Auto Battery Saver.

You should also get a compact rechargeable 12v jump starter, which provides the peace of mind of being able to drive your car.

 

I have something that I bought years ago that you plug into an outlet to trickle charge a 12V battery. I suppose I ought to haul it out to make sure that it still works.

 

All I need is the jump starter. This one from Harbor Freight is 6" long and starts the Kona just fine.

 

Just noticed this thread and poll. Everyone who has had a dead 12v battery should at least answer the poll, and maybe post there. But please keep that thread short.

 

I was going to make a new post but though it might be better here. There has been a software update reported on FB, one in the US and one in Canada so far, both cases where the dealer calls by phone and says it's a "recall". One owner posted a list of items affected that seems to cover most if not all of the Kona's subsystems including the LDC. I've translated the acronyms here:

1) BMS battery management system, 2) MCU motor control unit, 3) VCU vehicle control unit, 4) LDC aux battery charger, 5) IGPM (seems to control all the smaller items like power windows, what everyone else calls a BCM).

I'm wondering if this (LDC) is a fix for the 12V battery problem? Both Hyundai US and Canada have a VIN utility on their websites, so y'all can check for applicability.

 

Looking up my U.S. VIN here, it says there's no "Safety Recalls and Service Campaigns" for my car.

Got a link to the FB post?

 

Likewise no recall for my Kona on the Canadian site

 

One is near or at the top of this international group, the other a bit further down: Hyundai Kona Electric (EV).

 

I think we finally have some explanation of the 12V Aux battery charging algorithm for these cars. See this 2012 Hyundai patent.

 

Raised back in Feb from post #58.

 

We will hopefully get some feedback soon especially given that Canada was the first to receive the updates. You can only imagine that in order to monitor the traction battery more frequently that the system will wake up more than the current once a day for the battery saver. It will need the LDC to power the BMS, which means the additional possibility of assessing and/or charging the 12V battery as well.
I would guess that the applicability of the yellow indicator will not change. I might call the dealer soon and see if they have visibility to the updates, although as you say, I could wait to avoid the disinfection thing as well.

 

I would assume that the battery saver+ is now always on. Since anything else wouldn't make any sense. Maybe they changed the timing and/or length of the charge as well.

 

I joined after reading this interesting thread. I think my 12v battery is not being charged, despite having the Aux Battery Saver + set in my Other Features, except when I am charging the main battery. Is there a simple test I can do to check this, other than putting a voltmeter on it every few days? I never see the LCD display message shown on p H61. I do very little driving because of UK lockdown, and the other day it wouldn't start until jump started. Who woud have thought you need to jump start an EV? Another question: some contributors to this thread talk about leaving the car in 'run' mode to charge the 12v battery. What is 'run' mode? Presumably not the one where the little green car is ready to move

 

You could also use utility mode. That will keep charging your 12V battery forever (at progressively decreasing current but constant voltage) based on my experience with eNiro. You can read my posts from several weeks ago on the UK forum for more information.

It's not a very efficient charging method because the rest of the car is also powered up so wasting kWh to charge the tiny 12V battery. Better off getting a smart charger.

 

I've never seen the message either, and Aux Battery Saver definitely runs and charges my 12v battery (most of the time).

However, a dead 12v battery is a common complaint with the Kona EV as well as other Hyundai/Kia EVs.

Taking it in to a dealer is a waste of time (I tried once) since they can't duplicate the problem unless you leave the car indefinitely, and even then they won't know what happened or what to do about it.

I bought a small "jump start" battery pack and am living with the problem until someone says there's been a solution. It doesn't need to deliver much power, just about 30A for a few moments until the car turns on.

 

I've never seen the message in my car dash either but I've seen the indicator in the front grill Hyundai logo light up.

I've never had my 12V battery die, but I happen to have a little jump battery as discribed by others. I didn't buy it for those purpose but it's nice to know it could be a life saver.