How to avoid a flat 12v battery in a Kia EV6 or Ioniq 5 

Soul EV owner here, car currently at dealer to see if they can sort this problem - I will be very surprised if they do ! All those things you are saying, dash cam, boot light, seat adjustment ... should not be causing this to happen- they don't happen in an ICE car with normal use. And also, the ICE car has to then, crank an engine. A dashcam feed should be done with the correct feed cable, with inbuilt voltage cutoff. NextBase and Blackvue supply these. In any case - my car battery still died whether dashcam was connected or not! Also, I took the bulb out of the boot light, and turned off the inner dome lights (even removing those bulbs for a while ) ... battery still died. It should be possible to run infotainment for at least a short while - 10-15 minutes at least, without causing battery collapse. A battery collapsing like this, is baloney. There is some other problem going on. I used the Battery Monitor (same as Andrew Till) which was very useful to get some data about what was happening. Sometimes battery would hold charge for a long time, then suddenly voltage and power in battery would collapse. Some of the EV forums talk of a 5 Amp draw on these batteries - after car is shutdown. That's like 2 or 3 standard 21Watt brake light bulbs working. An ICE car starter motor draws in the region 100 to 250 Amps while cranking an engine. So, either, there's something very odd drawing this current to flatten the battery. Or the batteries are rubbish. Certainly, on the Soul/Niro/Kona they are too small. The new 2022+ Niro EV has a larger 12 volt battery than the previous Niro (about 30% more power ). Also, your assertion that replacing the lead-acid battery with a lithium one, would be too expensive ... should not be an issue with a car at the price point of an EV6 ?? In any case, it looks like this debate is going to go on for a while until a more solid solution is found.

Another really useful video. Thanks!

excellent video. clear step by step procedure.

Hello from France. New owner of an EV6, your videos are VERY helpful 👏🏻👏🏻👏🏻

Hi Brian - getting my ev6 next week. Thanks for the videos.

Kia EV6 here. That was a very informative video. I recently picked up a NOCO X45 jump kit to avoid the lockout issue; also handy for jumping other cars without straining my own car's electronics.

Hi I’m new to a Kia Soul EV and have found it quite a steep learning curve! I’ve looked at a number of RU-vid clips and not found them very helpful. Then, I stumbled across yours and find them excellent, very clear and helpful…thank you!🙏

Great video. I agree with you the jump starter is a must have accessory. I bought mine as a precaution in case I get a flat battery but as yet not needed on my e Niro thank goodness . But had to use it on my sons car not to long ago. Plus you get a power brick to charge your phone / iPad in an emergency. I plug my dash cam into the cigarette / 12v socket so as the car is turned off the power is cut to the dash cam.

Hi Brian, Having watch this video , and followed your advice , I was prepared when my EV 6 12v. battery started to die. Last week it decided to do it on the I O W ferry! The guy in the car behind me seemed quite impressed. Keep up the good work. Jonathan

Thanks

Thanks for the video. Seems really important to know the difference in accessory mode. It is a 12v lead acid automotive battery though... Any basic one should be able to run the light (led or not) in your trunk for a day. Seems like the real ev6 battery drain problem is related to its electronics or it's onboard computer not shutting off.

Owners on the Kia EV6 forums recommend getting an Ohmmu LFP 12V battery. It's not cheap at $500, but it's a long term solution, and it weighs 20 pounds less than the factory lead-acid battery. It also has a larger reserve capacity.

I have a Kona EV had this issue twice now, second time the 12V battery was dead and wouldn't hold a charge at all, which on an 18 month car is not very good at all. There are loads of videos online with similar problems, still amazing that Kia haven't got this sorted. The battery booster should be a standard accessory supplied with the car in my view, better still the manufactures should sort it out once and for all.

Thanks for the video. Very helpful. My issue (again with EV6) was precondition for departure, and charging schedule set to off peak only ending at 4:30 am. Resulted in draining the 12v battery to pre condition the car. As I have not been to work this week, the battery is now completely flat - even though the car is fully charged

Hi Brian..Thanks for another great video..I have a question for you my ev6 front windscreen keeps fogging up do you have the same issue with your ev6 and is there any way around it.. tried all different options and settings with no joy any help much appreciated 🙂 👍 keep up the great work 👍

8x AA batteries should start an EV. There's no load from a starter motor.

Great video! My 12V battery wouldn't start my '22 EV6 Wind here in the US. The same thing happened about a year and a half ago, and the Kia Roadside Assistance folks sent out a service person who jumped the car and things had been well. This time I tried to jump the car with a 12V battery that I use on my boat. The jump "worked", but once I unplugged the battery I got a message that the 12V battery was low, and the car went dead again. I called Kia Roadside Assistance again and was told to NOT JUMP THE BATTERY. They sent a tow truck and the drive had explicit instructions to NOT JUMP THE BATTERY. Car is at a dealer and it will be interesting to see if they replace the battery for free or do anything to the charge control system.

LOL ! Too funny. Can you imagine going through that on your way to the hospital?

Hi great video , daft question but will any regular 12v charger work for this ?

Thanks Brian for this very helpful posting. Here's a question: I had a Lotus M100 S2 Elan, which used a sizeable amount of 12v power when switched off and was a nightmare to get into when the battery was flat. I used to spend 3 months away from home so to avoid the battery problem, fitted a recommended CTEK XS battery charger & conditioner permanently wired to the 12volt, left it plugged into the mains when away, and never had another problem. Having seen Andrew Till's flat battery problems, when I bought my wonderful EV6, I got the dealer to connect the CTEK to the 12v terminals and it sits neatly in the frunk. I have never used it to top up the battery but next year will be a month away from home. Would you recommend plugging it into the mains when I spend that long away, just to keep the 12v battery tuned up?

Great video, thank you. Question ...is there a switch / setting to enable the 12v battery to be recharged from big battery ? used my booster pack for the first time yesterday bought after having RAC out 5 times in a week.

Good Video - Just a thought but the OBD reader could very well be killing the 12 volt battery - thanks

@5:00 or so that’s not quite right that the accessory battery has no BMS. My apologies if you’ve already found all of this out since this video is a bit old, I know some of it came up in your next video. The 12V battery doesn’t have a BMS built into it like a GoPro or drone battery, but the car implements one in the VCMS based on the voltage and a current sensor on the negative terminal that monitors all current in and out. CSP actually has a 12V battery SOC PID reported by the car, which is the source of the in-app telemetry you mentioned as well (the API actually gives precise SOC, even though the app doesn’t). I know you found the 12V dashboard in the next video. Watching it closely reveals that the LDC doesn’t merely top-up the battery and come what may as for load - it takes a very active role in managing charge in and out, often I’ve seen going as far as to keep a precise mild drain or charge on the battery for whatever reasons it has. Finally, the car does NOT have to be on for top-up, and the overnight orange light isn’t scheduled. The VCMS continuously monitors 12V SOC and activates the LDC to charge it any time the SOC hits 80% or below. Why, then, does it seem to go flat so often? Unfortunately, the system logic (called Aux Battery Saver+) is just rather dumb. It will ONLY top the battery up 10 times in a row (meaning no drives or other power-ons between), and when it hits 10 it blindly assumes the battery is faulty and stops trying ever again (this is spelled out in the manual, not that it makes any sense to a layperson or indeed even an engineer). It doesn’t matter whether the load is legitimate (like using the app a lot) or third-party (like a dash cam), even though the VCMS can directly measure real current in and out of the battery.

We just took our 7-month old EV6 for a complimentary maintenance yesterday. They found the 12V battery only at 30% capacity and replaced it under warranty. One of the advice they gave is to keep the car fobs distance away from the parked vehicle when at home. Because the fobs remain "communicating" with the vehicle even when it is parked and locked, sitting in the garage. :(

I believe leaving the bonnet open for long periods also drains the 12v battery. Recently I had to take my EV6 in because it wasn't charging (this took 6 weeks to fix but that is another story). I got a notification from my Kia connect app warning of a low 12 volt battery whilst the car was at the dealership. I also noticed on the app that the bonnet had been open for about 20 Hours so rang the dealership. Unfortunately I got through to a sales guy who was less than helpful. Being a Saturday he said there were no service guys available and there was nothing he could do. He advised me to ring back on Tuesday when the service team would be available. When I pointed out the battery would be dead by then he said to ignore the notifications. At this point I asked to speak to a manager. After putting me on hold for about 60 seconds he then agreed to walk the 20 meters into the service area and close the bonnet. Not very good customer service I have to say

Have you considered adding a remote battery kill switch (used in old petrol cars having parasitic battery drain)

I have had to use my Noco GB40 about 5 times in the past month. Works great on my Kona EV. Not too much of a pain, but am concerned that eventually it won't work. 110 K on the battery and thinking it may just be time for a new one. I've had to fast charge enroute numerous times in ~-10C weather, therefore, I am running the heat while the main battery is not on and able to charge the 12v. Suspecting this is why it my just be time for new.

Great explanation but Worth pointing out this sometimes this doesn’t do the trick. Had it today you have to disconnect the negative battery terminal to reboot the car then charge the battery. So worth keeping a 10mm spanner in the car as well.

Hi can you advise which OBD1 do you use? Thank you

There are more 12V battery parameters in CarScanner: Aux. Battery State of Charge (SOC), Aux. Battery Current and temperature. If you update the Dashboard (Dashboard/Reset to default), 12V sensors are displayed on one of the screens.

My experience with my EV6: Under normal circumstances, the high voltage battery management system (BMS) should take care to keep the 12 volt battery topped up. I have installed a battery monitor device on my 12 V battery and I can see this happen when the car is parked in the garage. HOWEVER, if you plug in the type 2 charging connector, the BMS will no longer manage the 12 Volt battery. It is assuming that the 12 volt battery will be charged from the incoming charging voltage. That is all fine if there is actual charge coming in. The problem is that if you have a smart charger such as Zappi, it might be waiting for enough excess solar output and thus not actually charging the vehicle. So if you have parasitic loads on the 12 Volt battery, they will drain the battery if the car is left waiting for charge. If the type 2 connector is unplugged, the BMS will resume management of the 12 battery charging and will top it up as needed. There are threads about this in the Zappi forum, where a bug in the Zappi (now rectified) was discharging the 12 battery when the Zappi was put in STOP mode. Just my two bits worth... 🙂

thanks for your video. I just wandering if we can recharge our EV6 12V using charger like other non-EV？

Just FYI, in the states, the Kia app does not have a 12v battery status, at least anywhere I have found.

If you have your car parked at home and the 12v is flat, can you open the charge port door to plug in your home charger? I'm assuming it will need power to open it unless you can use the manual release by dropping the back seats and crawl inside to access. I fitted a BM2 to the 12volt on my Ioniq 5 and it does show it charging at regular intervals, so far without issue. I checked with my local Hyundai service manager who said that fitting such a monitor wouldn't affect my warranty but connecting any sort of monitoring device to the panel inside the car might, ( as shown in your video). He said that Hyundai's diagnostic equipment can tell if you've previously plugged in such a device. It might be worth asking your own service department before fitting such a device so you don't give them an excuse to deny a warranty claim!

Do you know what actuates the little light in the frunk/froot of these Kias? I wonder if sometimes it's stuck on and that drains the 12v? Maybe if a car seems to drain too quick perhaps record video with your cell phone and pop it in the frunk and close it. If it records the light is still on, that's a problem.

is it safe without disconnecting the Main battery to 12v connector in the fuse box while doing this?

Any car that can’t top up it’s 12v battery without needing to be turned on is just wrong. Some cars are capable of using the HV battery to charge the 12V battery when needed.

If you going to be home for extended periods of time example off work days so two days home car parked in garage no usage…couldn’t we start the car and “idle” it for 5-10mins will make the main battery charge the 12v battery? Sorta like the alternator charging or keeping a combustion engine battery alive till you get a replacement or full charge… Any thoughts?

The Bluelink for IONIQ 5 does not show the status of the 12 V battery. Hyundai left that out. :-(

This has been an issue for eight years to my personal knowledge. I have always preferred to use preventative maintenance rather than cope with an inconvenient failure. I use a smart charger at least once per month that initially puts the 12v battery under test - then goes through a conditioning phase to repair any issues seen and only then goes through a series of planned charging regimes to fill the 12v battery. An old dumb charger wont do that and neither will a trickle charger. I know it shouldn't be necessary but life's too short to stress over such things.

Status / Others / details on the connect app does not show the 12v battery. Only doors, tailgate, bonnet, charging door and lamps. How do I get the 12v battery status to appear?

Do all dashcams drain power when connected directly to the 12v ? I ask cause my kia dealer offer to connect a dashcam they sell when we collect car?

There is another way of checking your 12V battery. I bought a cigarette socket Voltmeter, this monitors the 12V system whilst the car is running. I have seen the voltages down to 11v! It also has a USB socket into which I plugged my Dash Cam.

Interesting stuff. However, you don't quite get the voltage observations right. Maybe you're just not speaking precisely, or maybe you misunderstand, but... Nominal voltage for a 12V lead-acid battery is 12.6V. When you see higher voltages on your display, that's because some component in the electrical system is charging the 12V battery. Thus, when the car is turned completely off, the voltage drops immediately to something in the 12 to 13 volt range. Likewise, when you turn the car back on after depleting the 12V battery somewhat, the voltage jumps up to 14V. This is not indicating that the 12V battery has actually been "topped up" immediately, as you state in the video, but rather that the 12V battery is receiving a higher charging voltage to restore its charge state back to full. I don't know all the details about how the EV6 12V battery charging system works, but it's conceivable that once the 12V battery is completely full, you'll see a voltage higher than nominal, but lower than a regular charging voltage, if the system does any sort of "trickle" charging. I doubt this is the case because the owner's manual and other documentation always discuss the charging system making decisions to charge the 12V battery when it gets too low, rather than just trying to keep it topped up all the time. But I don't really know for sure.

Kia put a substandard 12v battery in there ev,s, I changed mine to a better battery and since then I have had no problems with mine going flat ever since.

Has Hyundai / Kia fixed this yet? I am considering the purchase of an Ioniq 5.

Can you jump from an ICE 12v battery?

Thanks so much EV Odessey. 👏🏼 Received my EV6 GT Line S in June after a 14month wait. 🚗⚡️ Been following you for about 6months. With great interest. This Sunday I experienced the 12v battery frustration. No response from remote. Manually opened the door but dead inside, no response. 🔋🪫🤷🏻‍♂️ Followed your links and ordered what looks like the Battery booster from Amazon for £50. Connected it up and got the green flashing lights. Took me far to long to find the boost button on the connector not the booster battery 🤦🏻‍♂️ i had the emergency light flashing away. 🔦 EV6 responded and took it for a 40min drive. Next morning no response again 🤦🏻‍♂️ so boosted and drove to local train station for work. Return 11hrs later and car started perfectly!? 🤷🏻‍♂️ Working from home Fri but will check it out as i plan in using on Sat. ⏳🤷🏻‍♂️🤞🏼

The cabin heater element should run off the main battery and the blower fan should run off the 12v battery. The small 12v battery does not have the capacity to run an energy hungry heater element for extended periods. 👍

I've never had any issues with our Air, probably because it doesn't have things like powered tailgate, electrically adjustable and heated rear seats. ICE car batteries have always been iffy in the winter, even though they benefit from an alternator topping them up whenever the engine is running.

Is it true that if the Li battery is below 20% the starter battery may not charge?

all ev6 have V2L, is it not easier to use this function and a standard starter or battery charger? Or v2L is not active with 12v battery empty?

You say don’t get the dashcam wired in to the fuse box. What is the best way to run a dashcam in an ev6?

My Hyundai Ioniq 5 is at the shop for an on-going battery issue. My 12 volt is dying regularly. My booster device worked a couple of times, but now, it fails to start my car.

The 12v battery is simply not being stresses or stired. on a ICE car the act of starting the car causes a short circuit in the battery and asks for its maximum draw / output this prolonged action stops sulphation of the battery plates and keeps the battery fresh in a EV the current draw is very low so sulphation starts. if you purchased two battery's fitted one to a car and stood one in the corner of your garage the stood battery will be totally useless within 1 year battery's that are used every day will last longer. the long term answer for this issue is to move to a lithium 12v which internally works in a different way and will cope with this issue.

Octopus Energy has suspended its intelligent tariff while investigating why it is killing the 12v battery. As I'm a member and experienced this I'm still able to charge for the 6 hours between 11.30PM - 5.30AM. I've disabled any intelligence for now 🙂

All Kia needs to do, is add a hidden button in the cabin, that starts up the DC-DC converter, and charges up the battery to get you out of trouble.

Also I thought, you are not suppose to connect the Negative battery.. you clamp it on a grounded metal within the chasis.. You only connect the positive to positive.

I avoided the issue, I didn't buy one! UPDATE 7/10/2023: NHTSA has opened an investigation into the 2022 Kia EV6, which joins the Hyundai Ioniq 5 under a probe of loss of power during driving. Both EVs have been the subject of owner complaints that power is reduced or lost completely while the vehicle is being driven.

My 2020 ioniq 38 it's the third (3) 12V battery unit... shameless Hyundai/Kia

Thanks