IONIQ 5’s 12-volt battery is dead: here's how I jump-started it

[@chrisrowe22]

I’m one step ahead of you Andrew. I’ve got my jump starter stored in the frunk! Haven’t need it so far!🤞

[@Martinedo_]

but can you open it if the car is dead?

[@chrisrowe22]

@@Martinedo_ Yeah, the frunk has a manual release. That’s why it’s in there, and not in the boot!

[@Martinedo_]

@@chrisrowe22 great. I see you commented last year, did you have to use the starter since then?

[@chrisrowe22]

@@Martinedo_ No, never needed it….yet! I’ve sold the Ioniq 5 now and have Tesla Model Y, but I still keep the jump starter charged up and stored in the frunk.

[@mfurmyr]

I had 3 batteries on my e-Niro on 112 000 km as a taxi. They were replaced free of charge. No problems on my Ioniq 5 RWD. Keep the charger in the frunk.

[@EV-olution]

It really is amazing the Hyundai and Kia have not learnt from the Kona and Niro 12V disaster, especially since the Kona received and updated software to fix the issue. You would think they would have implemented a similar programming to the Ioniq 5. Also, this is why I leave my booster pack in the glove box.

[@letsgetmg788]

*learned

[@paulfisher7303]

I am not sure that they really acknowledged the issue.

[@noleti]

i also had issues on the even older soul ev. so this is around since 2015 or so

[@MovieViking]

They have learned, at least on the Hyundais it's in the FW-code, but something else is still going on with the EVs randomly experiencing a 12V-drain without the battery being charged accordingly. I get the message that the "aux battery has been charged" message three or four times a week and without exception if the car has not been driven for more than 24 hours.

[@EV-olution]

@@paulfisher7303 the 2020 Kona Electric received an updated software that changed the 12V maintenance charging patter from several hours to every hour.

[@mikek2218]

One idea is to get a deep cycle 12V marine battery rather than the "starting" batteries that all new EVs seem to come with. You don't need the high amperage kick that ICE vehicles need from a 12V starting battery. But what EVs do need is the deep cycle storage that marine batteries have. I replaced the starting battery in my Nissan Leaf with a deep cycle marine battery, and it has been golden.

[@MrErus]

Don't forget if the drive chain battery fails the essentials such as powersteering & brakes will use the accessory battery, so just make sure it'll provide the necessary current.

[@irekfilms]

Thank you .The size does not change anything but it’s very confusing some manufacturers stating groos sizes some netto better sizes. This should be sorted in the future so that anyone knows. From the very beginning everyone was telling that the usable battery in Ioniq5 is 72.6kwh now it looks like 70 kWh even more confusing.

[@MovieViking]

@@irekfilms No, the 72,6 kWh is what is made available to the driver by the BMS. It's not confusing, but why you are bringing this up in a thread about the 12V battery is...

[@rkan2]

EVs need to figure out their fucking battery charging. There is a very good electricity supply with a good working battery charger. Why would you not just charge the battery when it is going low?? I don't understand it...

[@flames4494]

@@rkan2 thats not how 12v battery cells work

[@philipm3776]

Thanks, Andrew. Ordered a jump starter as soon as I had watched this yesterday, which is now charging in readiness . . . Back in October, I asked my Hyundai dealer to charge the 12v battery as part of the PDI, as I had read of problems with the batteries discharging during transit. I was grandly told by the service manager that they couldn't, because the Ioniq 5 didn't have a 12v battery! When I sent them the relevant page from the owner manual, they then sent me an email telling me how to access the 12v battery - which I had just told them. Messaged them a week ago to ask for a firmware update; received an auto-response but nothing since, despite e-mailing a reminder. This is my first Hyundai and my first EV. On the basis of the dealer experience so far, it might well be my last Hyundai, but I like the EV driving, so thanks for your various informative videos, which encouraged me to take the plunge.

[@MovieViking]

The quality of the Hyundai dealers is - to put it politely - uneven... I live in Denmark and within 50 km there's both a really, really bad and incompetent dealer (with an even worse repair shop), a fair one and an absolutely brilliant one. The good ones will help with anything and they even cooperate with the official agent to help people in a bad situation with zero warranty due to their car being unofficially imported by people speculating in the waiting lists.

[@MattMcIrvin]

I wonder if they were confusing it with the old Ioniq hybrid, which actually did not have a separate 12V battery. (I think it is weird that they took this seeming step backward.)

[@guyhenry3047]

@@MovieViking I recently made a service appointment at a local Hyundai dealer (not my usual one) to replace some peeling, vinyl door trim pieces, and the young lady asked if I also needed an oil change.

[@susiebishop3956]

Thanks so much. We were stuck in an underground car park in Belgium with no other option than calling for recovery until we found this video! ❤️❤️❤️ Your advice saved us!

[@MrEV]

That’s wonderful to hear! Do make sure you take your car to the dealer so they can install the BMS update. It should solve the issue going forward.

[@mowcowbell]

I keep a Battery Tender 12v charger in my garage and hook it up to the 12v terminals on my vehicle once a month or so and let it trickle charge overnight. So far, my 2018 Honda Clarity has had no 12v issues with the tiny OEM battery that Honda installed at the factory. I agree, the 12v jump pack is a must have for any owner. Simple jumper cables won't help you if your car is parked in a tight spot where a second vehicle can't pull alongside to provide a jump start.

[@basementstudio7574]

Not just a Hyundai/Kia issue. The Polestar 2 has this same problem according to the many posts on the Polestar forum. I just can't wrap my head around why it's so difficult for these manufacturers to get the BMS to recharge the 12V

[@MrErus]

Whilst not a 'pure EV' the prius (yeah I know everyone hates them) has the same issues, drives me nuts, as you said why is there no simple BMS keeping the 12v recharged?

[@daemorhedron]

Think the issue is that despite the rest of the car evolving, they still slap in a classic, old, heavy lead acid battery for the 12v side. Think a real fix is not just BMS, but to update this to LFP instead (believe Tesla recently made this change).

[@Tom55data]

@@daemorhedron No, that is a stupid idea. The reason that EV's use lead acid battery is that a 12V battery is constantly charged and discharged in both an ICE and EV cars due to alarms, and other ancillary items even when off. This means that the 12V battery is treated very badly and constantly cycled. There is often high discharge rates too. The 12V lead acid battery is the best technology for the problem, but is still a weak link in ICE and EV cars. People who tried to change their lead acid to any lithium technology usually kill the replacement in months, and EV battery should last between 2-5 years (like an ICE car).

[@smijas]

I'm conviced that these BMS/SOC problems were not causing any problems in ICE's with their always running engines. The 12V equipment was needed in an EV and the whole system was just copied to the EV. Only one new module, the DC-toDC converter to charge the 12V battery. Problem: No active monitoring on stand-by or when the car is on-charge, only monitor the SOC of the 12V when driving (like in the ICU, like if controlling the load-parameters for the modern alternator in an ICU) : problem - The 12V systems of the EV drain the 12V battery more than those of a locked ICU car. These problems are fixable, given the right parameters, use-cases, budget and the WILL to solve them.

[@circuitdotlt]

Not just to recharge, but also don't run various systems at 100% cpu load when parked. Which I'm sure they are doing. They were probably rushing these cars out of factory and were planning to fix the issue later. If ever. I remember this happened to tesla roadster in 2013 and that was a huge thing. Can't believe this is still happening.

[@spektrograf]

Sorry to hear you're starting a new 12v saga. Your previous series has me wondering about my Niro EV. Hope it doesn't turn into a multi-month challenge. On an upbeat note, I love the videos with you and your wife. They're informative whilst being pure comedy. Thank you for the great content! ☺️🍻

[@douglasturnbull6989]

I have had the problem with a Prius PHEV and understand it happens with the VW ID3 as well.

[@leesmart1971]

3 years and 32,000 miles of owning my Kona without 12v battery issues. I've enabled the 12v battery saver option and occasionally see the yellow light on the H logo in the front illuminated to indicate the car is topping up the 12v battery. Lucky I guess.

[@maxsec2]

not to jinx it, but same with the e-nira that is 2 months younger than Andrew's...

[@Joe-lb8qn]

Lee what is "the 12v battery saver option" ? Thanks.

[@alistairl]

Looking in from the outside this is almost a rite of passage for every EV i.e. the 12V battery causing issues. Thanks for keeping us informed.

[@jhawkins2049]

On my 2nd BMW I3, current one almost 4 years old, never a day’s problem with 12v. Given that many people had a similar problem with eniro it’s about time Kia/Hyundai sorted this problem which is all down to battery management. Inexcusable!!

[@alistairl]

@@jhawkins2049 I've read about the early VW ID.3 issues and James May's Tesla Model S having 12v issues. I also see the Model S Plaid has a different 12v solution. As you say it isn't the most difficult problem to solve on an EV Platform.

[@ellistreloar2047]

@@jhawkins2049 The question of 12V issues in the E Niro is a myth. I suspect that Andrew has drained his 12V with accessories attached with the motor and utility mode off or failed to close a door/boot. The E Niro is the second most popular EV in UK and EU so lots have been sold, including to naive new EV owners. Some - TLDR the manual - assume that the car’s electrics are always powered by the bloody great 64kWh traction battery. They use accessories, infotainment, lights etc with the motor or utility mode off and they drain the 12V battery. ALL 12V car batteries will perform badly if they are drained including EVs. I. this video Andrew admits the E Niro fault only occurred after he had drained the 12V by using an attached accessory. Two polls about 12V batteries on the E Niro owner’s group (2500 members) proved that less than 10% of members had any issue. All the individual posts complaining about the 12V in the group eventually admit they drained the 12V from ignorance.

[@jhawkins2049]

@@ellistreloar2047 fair point, but I still think there’s a problem. There’s no such thing as utility mode in the i3. I use infotainment, lights etc etc as much as any eniro owner and have never experienced any 12v problems whatsoever. The car is sitting on a huge battery reserve. It should be a simple fix for the drive battery to keep the 12v topped up as and when necessary. There is no reason whatsoever for people to be able to drain the 12v. Utility mode or whatever should be completely unnecessary, as it is with BMW. It’s all down to software and proper battery management. It’s a disgrace that people with £45k cars are buying battery monitors and jump starters. Mine will be going straight back to the dealer.

[@ellistreloar2047]

@@jhawkins2049 The point I’m making is that the number of people reporting 12V problems in the E Niro group is less than 10% and going by the individual posts faults are caused by owner’s error. 90+% owners have no need to run utility mode to keep the 12V topped up. The E Niro BMS regularly tops put the 12V either whilst driving or when the car is parked, as necessary. During my winter monitoring when we were driving only short journeys, 4-8 miles, I observed the BMS maintaining the 12V between 65 and 90% SoC with charging typically taking place overnight. I would regularly see a single green battery light flashing on the dash from outside the car, which indicates this mode.

[@stefanwhite782]

Has happened 3 times now in our new Kia Soul. Same as yourself: after a longer journey or after at least >100 combined miles. Many thanks for your previous videos about the e Nero 12 v issue; they saved us a lot of stress. We are hoping Kia will replace the 12v battery…..

[@ev6-joerg]

I think this is the typical Ioniq 5 problem I have seen many times on KZbin. Because of the charging port cover is closing to hard, the closing button is permanently pressed, which is causing a trigger loop in the software logic. So the battery gets down after some hours. So, this is a known issue, ask your Hyundai dealer. Some owners fixed this problem by fastening some pads between the charging port and the cover to prevent that the closing button is pressed by the cover.

[@MovieViking]

Brilliant, that could easily explain the drain. Thank you, I will pass that on! I guess your EV6 does not have the same "feature"?

[@ev6-joerg]

@@MovieViking No, the construction is another one and not exactly the same, but I think, I should observe this button and avoid pressing it to open the cover. I think the problem can be caused by often pressing this button, so that the restoring force decreases over the time.

[@Mat-hr1dg]

This is valuable info. On behalf of every owner that might read this, thank you!

[@rogermowat401]

Thanks Andrew for another refreshingly honest video. Totally agree how in this day and age where the technology you are driving is so accomplished are we still dependent on elderly lead cell 12 volt batteries to power ups he internal technology? Come on manufacturers get this sorted across the board.

[@vmfan96]

Unbelievable how this is an issue on EV's. Thanks for this video. It brings awareness to the issue. Why couldn't they have a built-in battery monitor that would alert you that the battery is critically low? Even better have a module that automatically comes on to top up the 12V from the high voltage/bigger battery. The smartest minds at Tesla couldn't fix this? sheeesh.

[@CLIVIGER]

I had the same issue with a 2022 Toyota RAV4 PHEV. Drove 200 miles and parked up on holiday for a week and didn’t use the car. When I went to load our cases the 12v battery was completely flat. Couldn’t open the boot or doors electronically. Had to use the emergency procedure to get in the car and then use jump leads to put the car in ready mode. Took it Toyota who kept it overnight but said the battery was ok, and advised that it was ‘normal’ for electric cars! I went straight to Halfords to buy a battery pack like yours which fits in the glove box (don’t keep it in the boot!). A couple of months later when we took the car in for a service we were told it needed a software update to tackle a 12v battery problem- surprise surprise:). Haven’t had the issue since but having the battery box in the glovebox sure is reassuring.

[@petercittern5898]

Hi, I've posted about this several times on Speak EV. My Ioniq38 had a similar issue and was in the dealer 4 times with dead 12v, I was about to trade it in as I was so fed up with it. However, in the nick of time, the 4th time this happened, by a fluke I noticed that one front door was locked and the was unlocked (this may have been the case on the earlier occasions but was not noticed). This gave an error code to the dealer saying there was an issue with one door lock. What was happening was water ingress into the front doors past the glass as normal was impinging on non waterproofed electrics (the mechanic said he had never seen that before on any car usually there is at least a plastic shield to protect the electrics). The car thought the door was open due to the water droplet(s) bridging the contacts and kept the car awake. I was getting lots of "you have left the doors unlocked messages" through bluelink which I had dismissed as nonsense since I could see the mirrors were folded in...... So the dealer waterproofed the door electrics and I haven't had a problem since. If this happens after rain or washing your car then look out! One time the AA came and were actually measuring a 2A vampire drain but couldn't say or didn't have the time to diagnose where it was coming from, they said the dealer will have to diagnose that. So, one close of the door, the droplet falls away and hey presto the evidence is gone! No idea why the error code didn't flag the other 3 times... "Friday afternoon manufacturing error" or not I can't say, as I know lots of people have similar issues but have said that at the time it happened to them it was dry.

[@CED99]

2A vampiric drain isn't good, that'll drain (potentially to the point of being dead) a 12V in under a day :( n.b. you shouldn't discharge lead acid batteries more than 50% (unless they are "Leisure" batteries Andrew mentioned), normal car batteries are considered to be “fully discharged” at 10.5 volts, discharging them further allows lead sulfate crystals to form that can't re-dissolve in the sulfuric acid, effectively shortening the lifespan of the battery in an empirically measurable way.

[@petercittern5898]

@@CED99 Agreed. That vampire drain killed the 12volt, the dealer replaced it under warranty

[@danielguve8351]

I have a battery in my Mitsubishi Colt Ralliart and it’s original from 2008! I cannot believe that it still works in the Swedish winter. Btw, my Ioniq 5 should arrive in march! So exited! 😁

[@andrewmalloy2274]

My wife's 66 reg Kia EV Soul has been having 12V battery issues, found it dead a few times over recent months, even had to jump start it from my diesel once. Bought the battery jumper you recommended, used it for the first time today, and it worked a treat👍

[@MrEV]

Great to hear!

[@MrWobling]

We've had 12V issues with our 22kwh Zoe - never been completely flat, but eventually traced weird intermittent electrical issues to a low ish 12v battery. Replaced it myself and problems went away. Think I worked out there was a time I was sitting in it reading a book while waiting for a rapid charge - kept opening the door to keep interior light on when the car went to sleep. I realise now this caused a big drain on the 12V battery which probably wasn't getting charged even though the car was plugged in and charging.🤦‍♂️

[@peterthomson127]

Watching with interest as I'm about to order an Ioniq 5 very soon, I will get my backup jumper too! At 2:29 you can see the battery rating plate - Hyundai are definitely fitting ICE starter batteries to their EVs, as your battery has a CCA (cold cranking amps) rating of 550A, which is all about the current surge it can supply to crank a starter motor. Totally unneccesary for an EV. The batttery should be a deep-cycle type, which will provide a steady current output for much longer than a starter motor of equal Ah capacity, or even better a Li-Ion type with greater capacity and less weight. But even so, there is clear a system design issue here. The 12V battery shouldn't be getting allowed to go flat at all, since charging of the main battery seems to depend on it. Would be interesting to see how Hyundai/KIA have modelled the partitioning between the high voltage drive system and the low voltage electrical system, 'cos they are definitely missing something.

[@johnmoylan7202]

an Odyssey deep-cycle battery (AGM) would be good for that.

[@boeingpete]

Came across this while researching battery problems with the Toyota Yaris Cross range of hybrids, and it seems that a flat accessory battery is to be a pretty common problem with a significant number of makes of hybrids. Poor quality batteries plays a part but personally I reckon the root cause is these car have so much tech running in the background 24/7, even when the ignition is off. I have a friend with a VW hybrid and he too had problems with the accessory battery going flat.Great video Andrew, with some useful comment and advice which every EV owner should take on board.

[@MrEV]

Thank you! And yes, I agree that the more I look into it, the more it's the software/battery management that seems to be at fault and not the battery necessarily.

[@philpix5]

Hi Andrew my Ioniq5 12v woes continue. Hyundai Assist(AA) out four times in two days! They confirmed the 12v was goosed and not accepting a charge. My dealer would not accept the AA findings and said to book my car in…..six weeks until the earliest slot. I have just simply replaced the duff battery for a new one. What is interesting the last AA patrol guy told me he was part of a team called in to help do PDI checks at Tilbury docks as Hyundai themselves could not cope with the work. He said the amount of replacement parts including main batteries was astonishing. As I mentioned before a great video. Keep on posting. You and your family keep safe.

[@MrEV]

What a ridiculous situation. Hyundai really need to pull their finger out and use better batteries - it must be costing them a fortune, both financially and in terms of brand damage. I hope things improve for you now you have a new 12v.

[@treezh5815]

I've just ordered a Toyota Yaris Cross and joined a few facebook groups to learn more about them. Nearly ever other post of them is about the appalling 12v batteries on them. So it seems like many evs/plugin hybrids and "self-charging" hybrids have the same problem. I spoke to the Dealership I am buying from and asked them what can be done. They say they will provide me with a solar charger that I can plug into the cigarette lighter in the boot to keep the charge up. They say that if there's a day I won't be using the car at all, to plug it in then. I have to unplug it when I get in the car next time. Not sure if that will work. But will give it a try. I've also purchased a noco battery booster to keep in the car just in case. Hope my new car will be worth all of this effort!!

[@sistagg]

After reading loads and loads of rambling forum threads and a bucket full of videos none of which really helped I found your video. Wonderful, and thank you so much for sharing a simple, straightforward solution. Cheers, Simon

[@MrEV]

Great to hear, thank you.

[@kilroyfilms7590]

Had this exact issue on mine, but realised after that I had stupidly sat in shopping park, waiting for the boss, with the radio on and my dash cam without being in ready or utility mode. I got a traditional jump start from a neighbour and now keep jump leads in the frunk, but after typing this will be clicking on your link to grab a battery... thank you :-)

[@frankgooding443]

The jump pack is great, lesson is keep it in the glove box. Shocked the 12 Volt i snot topped up by the main battery charger, pretty poor oversight. Good thing you are well prepared.

[@theseb1979]

Yes, that does seem pretty darn stupid since it happens when the car is driven.

[@nigelchubb7120]

I should have added in my comment a thanks for showing how to remove the cover over the battery. I cannot find this in the owner's manual. They talk a lot about charging the battery and removing connections but not access to the battery.

[@CeedFX]

Great video, I googled the reason EV car still uses 12v battery, lead acid battery to boot. There are actually some very legit reasons. One of the major reason is so your main lithium ion battery will not brick and costing you $20k-$40k to replace. Sorry you have to endure 12v battery a little longer until engineers figure out a good cheap solution for this. Meanwhile, I'm going to get that battery jump starter you recommended. Looks very handy even for ICE cars.

[@alanbrad3727]

Funny i just rewatched your last 12volt video. My IoniQ 38kwh was warning me this week that it was low before completely going flat yesterday. I jump started it plugged it in at work all is fine now! Booked it in but have a 2 week wait! I have put a battery monitor on like your Niro. Thankyou very much for this great info.

[@danielcussen4897]

I highly recommend replacing your battery now asap. Once a battery has gone that dead it needs replacing. A leisure type battery will recover better but for your own sake and peace of mind put in a new battery. On my ioniq 28kWh the battery regularly went flat, but usually due to boot bring left open or car not fully locked etc. After ot goes dead once replace it. It may have had a hard life already on the ship from south Korea.

[@ecoworrier]

I think you should connect the red first and black second, then disconnect black first. That is safer and you get fewer sparks when connecting.

[@rhysjones4500]

He should connect the red to the battery first, then the black to the provided point on the car body, not to the battery directly. Batteries can off-gas hydrogen so you don't want sparks anywhere near the battery if you can help it. Then disconnect the black first afterwards. If you understand why you're doing it, it's easy to remember.

[@andysimmonds4023]

Thanks for showing us what to do. I have already bought a 12V battery jump starter, but I'd buried it for safe keeping right at the bottom of my e-Niro's boot. Having seen you have to go over the back to get it I realised I would have had real problems getting it out of the boot in an emergency🤔 Have now put it in a bag just floating around at the back of the car.

[@dalroth10]

I thought the same thing. I reckon I'll store mine in the glove box, just in case!

[@moomintroll2067]

I would have thought that the most obvious place to store would be the Frunk - right next to the battery. If you have an AWD, you're not going to get much more in there :)

[@andysimmonds4023]

@@moomintroll2067 yes, that would be the best place, but the e-Niro doesn't come with a frunk. I'll add it to my Christmas present wish list!

[@alltogethernow121]

2019 Kia Niro owner - yeah this is a big problem in electric cars. 12 volt battery always draining, it's a real pain... Happened to me so many times, Kia will replace the battery (if they ever get any).

[@paulfisher7303]

I have deployed homeassistant and used the Kia and Hyundai plug in. Gives me lovely live(ish) and historic data of the 12v and much more.

[@nigelcharles511]

I had the 12v battery fail on our Soul. My jump start pack (which was identical to yours) wasn't powerful enough to hold the relay closed for the main battery to take over. In my case the battery had dropped to about 9v. Maybe if the 12v battery is low enough it sucks all the power from the jump start pack preventing the 12v system rising high enough for the 400v battery to take over. In the end I managed to get the system back to normal by using a 12v battery charger for 30 minutes. I now carry a battery charger as well as the jump start unit. I provided Kia with the graph off the voltage monitor app which they appreciated but even having had the car for a week they couldn't find the problem. The car has run since for 6 weeks without a problem but like you I don't trust it not to fail again.

[@heliharris69]

Been said before....But just how difficult can it be... to automatically allow charging of the 12v battery.... anytime or anywhere... by the main drive battery...When the 12v battery drops below 12.5 v....This whole saga defies belief......Great informative video.

[@howieb2001]

Your videos are an education. As soon as I get my Ioniq 5 back (no idea how long that's going to be) I will be making use of your tips and tricks. Thanks.

[@stephengerth1189]

My new KIA EV6 has the same problem. I had the problem once with my E-Niro got no start but a swarm of false alarms. My dealer recommended that I charge the 12 volt battery often with a traditional charger during the winter. He said that the system goes crazy when the voltage goes too low (11 volt he guessed). He also said that every time you open a door or punch in with the app the car wakes up the 12 volt system for 30-40 minutes. That seems to deplete the battery without waking the "charge me" signal. Good luck!

[@christophergrau4819]

Thank you so much for this! Got my Ioniq back up and running with your help. Lifesaver!

[@MrEV]

Thank you! I'm so pleased to hear that!

[@Danne89]

Most people in Norway (and here in Sweden) that had this happen reported that they had used Bluelink to open charge port. Somehow motor keeps drawing power then. So weird!

[@sebastientrudel4449]

First, I want to thank mr EV for the video: it’s a nice work around - I’d even say ESSENTIAL, sadly. Thank you for sharing, I feel less alone. ;) If you feel for some technical notes, I’ll try to keep it simple and not too stupid. So, like @michael s said: 12v batteries need to be kept topped up. I have yet to get and install a battery monitor / logger to see how much voltage /current is sent to the battery at any given time, but my guess is « not enough ». Sorry to contradict @flames (about 2 things, actually…) 1- a 12v battery should NOT be let down to 50% before it is topped off. That will only shorten its life span. 2- it should not be simply trickle / float charged because what appears to us as « always charging » (while you are driving), is actually a very small percentage of the time: think overnight, during the work day (unless you work on the road, and even then, the time spent traveling is probably

[@colingillan2399]

Same issue with my ioniq 5, was off the road for over 6 weeks waiting on parts from Korea. Was told that it was faulty charge door actuator and on board charger

[@cfldriven]

I'm really surprised to hear there are 12v battery issues with the current car of EVs. My 2017 e-Golf has an AGM battery and has never given me any issues. The car will turn off the radio if the level starts to get low, but putting the car in Ready mode starts the recharging process. Thanks for the video.

[@jeffgrave]

I own the 2019 Kona EV from Hyundai. SO ridiculous they have not solved this horrible battery management system. They had this issue way back in 2018 with the Ionic hybrid, then the Kona EV has it, now your demonstrating the Ionic 5 has it! I did a calculation, the main battery can keep the 12V auxiliary battery charged for 14 months!

[@rickchumsae7974]

We own two Toyota Prius cars. Our experience over 9 years of ownership of both is that Prius has a similar issue; the 12V batteries suddenly die. Because a hybrid 12V also does not crank a starter, there is no early warning that one often sees on an ICE car, which would be a slow crank on the starter if the battery was weak. Toyota compounds the problem in that, except for the latest model years, the battery is located in the rear boot and has a vent tube for gasses to move to the exterior... i.e., battery access can be miserable unless one crawls back to the boot area, removes carpet mats and under mat storage compartments and then releases the rear hatch latch. All, one hopes in the daylight. These odd ball batteries are specialized not just for the vent tube but they are also "deep cycle" batteries which makes them more expensive (by about 30%) over a standard car battery. This, even though the battery never cranks a starter motor. Prius 12V batteries tend to fail every 4-5 years depending on climate.

[@johnkeepin7527]

As an owner of a Yaris hybrid, it’s so far, so good after almost 5 years, but there are lots of warning notes in the manual, e.g. “Do not stop the hybrid system when the shift lever is in a position other than P. If the hybrid system is stopped in another shift lever position, the power switch will not be turned off but instead be turned to ACCESSORY mode. If the vehicle is left in ACCESSORY mode, 12-volt battery dis- charge may occur.” This one looks like a possible error by the driver - although in my case I never shut off the power without it being in P mode, and almost never use N, either (because it cannot charge either battery in that case).

[@rickchumsae7974]

@@johnkeepin7527 We too never turn off other than in park and only use N in a carwash, which we rarely enter.

[@stephenholland5930]

I bought a 12V USB charger socket which also has a readout of the battery voltage. It's usually showing around 14.8V when I check it.

[@laineracher250]

Thankful to have found your videos. I just bought an ionic 5 and was wondering what to do if this happened. Cheers

[@paulshepherd9886]

Always enjoy your informative videos. Puzzled by the comment on recommended jump starter "Please do not start vehicles when there is less than 50% of electricity left" Maybe its lost in translation. For what its worth, I have an E niro and no problems at all (20 months)but should be collecting Ioniq 5 in April and know several people who have had battery issues.

[@thomashenden71]

Hyundai has a very poor solution for charging the internal 12V battery, btw. I have a Hyundai Ioniq 2020 with multiple instances of dead 12V battery, where I did even got the excuse about the 12V battery being discharged due to smart charging. However the car should easily be able to refill the 12V battery from the traction battery, so that explanation is bullshit. I even got the explanation that my dashcam drew too much electricity which made the 12V battery go flat. And forgetting to close the trunk properly, should never be something that causes the car to drain its 12V battery so that it won’t start the next day. People (like me) have had a lot of 12V issues without this even happening, with no smart charging and no dashcam, these are just symptoms of a really poor charging solution of the 12V battery. So have we gotten EVs with huge traction batteries that cannot be used with dashcams and with smart charging, then? 😮 What really is the problem, is that Hyundai only charge the 12V battery with 12/72 hours intervals, when the car is parked, seemingly only rarely checking the status of the 12V battery. There is a mode called battery saver+ that must be turned on to make the period 12H not 72, however this depends on the software version of the car, some people have gotten an update where this mode is turned on all the time and the period is 12H. If you have this update or possibly on the Ioniq 5, you might not see this option in the menus, then it is "turned on all the time". Anyway, Hyundai lets the voltage of the 12V battery sink too far before charging it, then charging it only for an hour or so at a time, meaning the lifespan of the 12V battery will be limited. (Because sulfatation, look that up). Generally, the battery is 12.2-12.3V in the winter, so I sent the car back to the dealer, to have it tested, they claim they found no fault, after a really thorough investigation where they even told me that the dashcam didn’t take too much electricity. They reported that the voltage was 12.56V (which they seems satisfied with) even though it is too low to ensure a long lifespan of the 12V battery. The rest voltage should be 13.2 volt for that, then you get a 5-6 year or more, lifespan, while sulfatation occurs faster, under that and is accellerating when the voltage comes down further. My theory is that the engineers really planned for a 12V Lithium Iron Phosfate, not a lead acid battery, which indeed would work better with not being charged fully all the time. Probably it was cut from the design because those batteries are more expencive, and in cold climates, they neeed a heating foil. These batteries exist and will last the lifetime of the car, so it is incredibly irritating that we are stuck with these non-environmentally good lead acid batteries and EVs that won’t start in the winter because of this. My car dealer and Hyundai have certainly not been very cooperative about this, and there seems not to be any plans to update the firmware to at least charge the 12V battery often, enough… :-( And also - when you think about it, why would the battery saver+ function _option_ be needed in the first place, wouldn’t anyone want the 12V lead acid battery to be topped off, very often, to ensure its lifespan and that the car can start regardless of harsh winter conditions? The only reason to want to charge less often, would actually be if there was a 12V lithium battery which actually has a shorter lifespan, if it is topped up too often! This is me btw: www-tu-no.translate.goog/artikler/blybatteriet-i-thomas-elbil-blir-stadig-odelagt-forhandleren-skylder-pa-smartlading/524176?key=LDGUFGgP&_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp&_x_tr_hist=true And I must really say I am surprised that the 12V battery issue wasn’t even fixed in the Ioniq 5, so Ioniq is not recommended for colder climates where the lead acid battery is vulnerable, if you need a car that reliably starts in the winter. You can expect more problems next winter, especially if it is a cold winter, and replacing the 12V battery when it goes dead, should be a warranty replacement, the explanation that the smart charging provider polls the car too much, is just bullshit and in any case, it is a cellphone like signal, the load on the 12V battery should not be more than using cellphone and the click of a relay anyway, and this electricity should easily be provided by the onboard DC-DC converter / charger of the 12V battery. And also the claim from Hyundai that smart charging providers poll the car too often through the Bluelink api with "20000 times a day" seems very unreasonable - as there is 86000 seconds in 24 hours, meaning that the polling would happen every 4. th second - which practically is continous. This is not what I have experienced when waiting alongside the car. You can hear a relay clicking when a Bluelink connection is opened, eg. when you open the Bluelink app or does something in the app to change the configuration of the car, like starting preheat or changing AC/heating temperature, charging limits etc. and with my smart charge provider (Tibber in Norway) I never heard any excessive amount of clicking, defintitely not every 4th second, so Hyundai is really just trying to cover up that they made a really lousy 12V battery solution for these cars, most probably because they went with lead acid, not LiFePO4. Why they then, are not willing to at least let the car charge the 12V battery more often, through a software update, is a mystery to me, can they have made choices that prevents the problem being fixed through software, I don’t know, then a recall will be requiring physical work, replacing parts or maybe directly connecting to the hardware that needs updating, again, I don’t know. But I am knowledgeable enough about batteries to tell that a lead acid battery solution probably was not planned for, by the engineers, but was put through by the management, unfortunately, as it ruins this car that really would have worked well in cold climates, hadn’t it been for the 12V battery problem. I have also learned from Tibber that the voltage of the 12V battery is reported through the API, so Hyundai could at least have let us know through a push warning in the Bluelink app, that the state of the 12V battery is poor, but they don’t even bother to provide that. Also - for completeness, the 12V battery is also charged from the traction battery when the car is on, and when the remote AC/cabin warming option is on, however this is usually to short time, to reliably charge the small 12V battery enough in the wintertime. It is nearly 40Ah if I remember correctly meaning you can only access about 20-25Ah before the voltage sinks too low and damages the battery. Ironically - the car (12V battery) will usually survive hibernation which is activated after a few days when the car is unused, THOUGH Hyundai has gotten the not so bright idea that the 12V battery will not be topped off, if the traction battery goes below 40% SOC, so if you, as me, thought the car (and especially the traction battery) is ok at. 38-39% SOC when you don’t use it for some days, well then you are mistaken. And another car dealer from the same chain as I bought the car, even told me that they were not even supposed from Hyundai, to tell me about the 40% SOC limit! 😮 Now the car sits at the dealer, through the Easter, for checkup, and they didn’t bother to charge the car up a little after they depleted the main battery to 30% with their tests, and the Bluelink app will for some reason, not let me run the preheater, so that the 12V battery could have gotten a little charge, this means the ordeal of sending the car back to the dealer for testing, will have shortened the lifespan of the 12V battery furthermore! :-( All this mess have also made me to have to buy a jumpstart battery for my EV, something I never knew an EV would have to have, plus I will have to obtain one of these Bluetooth monitors for the 12V battery until I afford to replace the lead acid battery with a proper LiFePO4 batteries with the advanced winter functions and the heating foil, and they are not cheap. If you experience harsh winter climate, do not buy Hyundai EVs, neither the Ioniq 2018-2020 or the 5, possibly not future models either, as Hyundai has gotten 0 points of willing to fix or alleviate the 12V problem, so far.

[@peterhetherington914]

I had exactly same problem with my KIA e soul, had RAC come out and apply power to the existing battery to start the car, the chap then changed the battery for a better model. Like you I also bought a jumper.

[@fsr170409]

Hiya Andrew, I had a test drive in the Ioniq5 yesterday, was just about to go out and put my deposit on an ultimate RWD now I'm not so sure.Keep up the good work I think that you are one of the most honest helpful and informative person on KZbin,your videos are excellent.

[@MrEV]

Thanks very much! The wait time is so long for any EV right now, by the time you get it I'm sure it'll be fixed. Hyundai have acknowledged elsewhere (not to me, yet) that they're aware of a 12v issue and have been able to reproduce it. So fingers crossed, they'll sort it soon.

[@fsr170409]

@@MrEV Thank-you for your quick response, I do like the car it's the best EV out there at the moment. I test drove both the EV6 and the ID4 and the Ioniq5 blows both of them clean out the water. At the moment I have a Toyota CHR and it's a great car was tempted to wait for the BZ4 but I want something with more battery life. 🔋

[@JohnRoss1]

Maybe keep the booster in the front storage. Weakest link.. I purchased a similar booster. for the Niro-EV . Not needed in the almost 3 years I've had the car. Handy thing as my Lincoln hybrid car might need it. I've replaced several batteries over the past 10 years. They suddenly go so flat that there are no interior lights and there is an Airbag warning light. One morning our diesel tractor had a flat battery. I used that booster to just to test it (supposedly it should start a 4 cylinder gas car) . The booster did not have enough juice to to turn the starter but I could hear the fuel pump and fuel heater buzz. Probably good enough to turn on the 12 volt relay on a BEV.

[@2011ppower]

Had the same issue with my Ioniq 38 kWh, bought the cheapest jumpstarter from Halfords, and it works fine. I keep it in the side slot in the boot which is easy to reach via the back seat. I don't think you need utility mode just connect the jumper and start the car and off you go. However this does need fixing a nearly new car should start first time every time. 😠

[@sheepcute]

Actually early Ioniq EVs came with a Lithium-Ion 12V battery, as brand new Teslas are coming with. Those, I've never heard of any issues with. For some reason they went back to lead-acid though. Cost-cutting perhaps?

[@marvinsamuels1237]

It does look like cost cutting. We’re on our 3rd 12v battery and a replacement SOS module that was found to be draining the 12v battery. We were without our 71 plate Ioniq EV for 6 weeks while Hyundai diagnosed the issue and waited for a replacement module. Was using our trickle charger or other cars to jump start it, but going to invest in a jump starter. Hopefully we’ll have some trouble free motoring now.

[@ProfessorHamer]

That was the ioniq plug in hybrid, not the ioniq electric.

[@mr2times68]

Welp this came in handy, Thanks!!! I’d like to add that not all scenarios will turn the car right on so effortlessly. If the volts are low AND the car isn’t charged like 0% jumpstart as you charge until you’re at 2 miles. Once you’re at 2 miles test the battery to see if it’s at 12+ volts if so remove the tester to see if the jump box holds charge and remove as you continue your charge…You should be charging without alternative at this point. Good luck….👍 up ⬆️ the post if this helped or helps anyone.

[@wnhevenhuis7582]

I agree I am wondering why we still depend on a seperate 12V battery. From a engineering tedundancy argument I can understand certain scenarios. But even with an EV 0% battery still has more capacity than a 12 V battery to run basic systems. It would vastly make the car more aimplistic, less parts, just need aome smart design to be able to access systems with simole hardware locks in case of total system shutdown, and when plugged in the car just works to access basic systems while charging up. The managem3nt f breakdown would likely only then be limited to the bms board really. If that was in an easy accessible place for maintenace I would think these basic everyday issues woruld largely be a non issue. I hope that also makes some enigineering sense as well. I've seen many youtube videos that more people are increasingly replacing their 12 V lead acid with lithium ion batteries, even supercapacitors in ice vehicles. In any case, now you've shown it happened again on a new kia/hyundai vehicle, I think thos isuue has become serious enough for it to become a problem with the car and they should come with a permanent proper total solution, rather than a fix, to all current cars on the market and new releases to solve this. I think this is unacceptable, as you rightly said, with a modern ev, to have this issue like your current case with the brand new ioniq 5, and others. I can understand it os perhaps not always onevitable in the north european colser climates. Bit still, with proper management, which even was the case now, it is odd to have to deal with an underperforming 12v battety like yhis. I would consider it a serious design flaw.

[@DrPinball]

Thanks! This helps! We just got our car 2 days ago and I saw this warning. I just bought it from your link just in case. Have a great day!

[@sidweyz]

Would replacing the battery with a LiFePO4 battery be a good solution?

[@srichgtr]

EV6 has the same issue. Theories include boot not shutting properly so the car stays awake. But you'd think the app would warn that it thought the boot wasn't shut so the owner could shut it or tell the app 'yes it's shut, stop fussing'

[@davesutherland1864]

I have a Rav4 Prime and have had the same problem with it. The car did start, but ran as a pure ICE car (no battery use at all) until the 12V was charged enough to allow the hybrid/EV operation to start again. The dealer said I had to turn it on once a day or buy a trickle charger. I agree entirely with your sentiments that it is mind boggling that you can have a car with a multi kWh battery and it can't keep a puny 12V battery charged. I assumed an BEV would be a big more sophisticated than my PHEV, but you know what they say when you 'assume' something.

[@berthogendoorn2133]

Ok Andrew, my 2020 KIA Soul EV same problem, after the 5th time of going down to 7VDC or less, I charged it up and was going to drive to Kia to have them check it, we are a 40 minute Ferry ride (our cost) away from the closest service, again dead so I called road side assist and they towed it to North Vancouver Kia (on KIa's nickle). yes the diagnosed it, same as my Son who is a Red Seal mechanic concluded the battery diagnostic tool showed it was ok. We both agreed that killing a standard Lead Acid 5 times usually damage the battery. So after Kia service charged it up checked the DC / DC converter (and also see it was activating a charge cycle) they said it was fine. Ha, like lemons, so went home spent the same amount $300.00CAD on a High quality AGM deep cycle battery and it has been fine since, Yes Kia batteries are not suited for EV's.

[@joetheblowjoetheblowdave968]

Andrew you have been very unlucky with the 12 volt battery, however if this happens again have a quick look over your shoulder - if wifey is laughing at the window then need I say more !

[@MihneaStoian]

First time I hear of this. Had a Kia Soul for 3 years, no issues even when it sat for 3 months. On the I5 I see the amber light come on showing it's charging the 12v while stationary. I never park the car overnight with less than 50% charge.

[@erikhallin3026]

I have had this problem on my KIA EV6 three times. KIA has replaced the 12 volt battery once. They have not found any other fault in the car. What to do? Is it just to accept that this is how it is? I also have a Renault Zoe and have never had this problem.

[@shaunmckenna1923]

Very useful info as I have ordered the Ioniq5 but the wait time is long in Canada but the good thing they confirmed yesterday I will be getting a 2023 which means with all the updated .

[@judebrown4103]

Oh no! That's a real Victor Meldrew moment isn't it?! Andrew I can't thank you enough for being one of those people to whom **it always happens...! We are also of that persuasion and its so good to see how you deal with these things... including learning that perhaps the glove box is a better place to store the jump starter. 😂 Especially as we're neither of us as young slim and limber as yourself. Still another 18 months or so before we can make the change but I'm kind of leaning towards a secondhand Ioniq Premium 28kW as the best car for us, boot could be a problem but overall the pros outweigh that con. Good luck with the 12v, let it not be saga eh?!

[@danwiddon3854]

Keyfob battery issues (both of our EV, over 7 years) we have encountered, one recovery because circumstances conspired to leave me & my unstable Mum stranded in our 24kWh Nissan Leaf, but not failure of the 12V battery. Next time (if ever) we have a spontaneous failure of control systems, you've given me an idea of what might have gone wrong. Unconcerned about one car having no alternator, so thanks for tailoring your video to the range anxious followers still driving fossil fuel beasts.

[@timothyvenn4193]

Thank you so much for this video Andrew. I thought it possible I might have to do this sometime and your demo was as clear as a bell, I even have the same back up charger (having bought it for my previous Prius which gave me this problem a couple of times). I agree this is a ridiculous problem which they should have sorted out ages ago given the history on previous models.

[@bbbf09]

Very strange that so many clever engineers (presumably?) across so many EV manufcaturers and across the world can't get this 12V failing thing right. Kia & Hyundai not the only ones. VW's affected and others I have heard of.

[@petencalroberts7616]

Many thanks very informative, life is just as you see it it will dissallution all your hopes and leave temporal chaos.😂😂😂

[@lesliesmith6442]

My Nissan LEAF was 9 years old before I changed the 12v battery. It was still working fine, but I would notice the right blue dash light flashing more often, which was the car topping it up.

[@darkknight8139]

I had this exact problem on day 1 and day 2 when I just got my Ioniq 5. The 12V battery measured 3 volts. I should have known about the utility mode, the old fashioned mechanic with the jumpstarter said that I should have a drive for half an hour. I think that the battery management system for the 12V battery is not turned on often enough. It should turn on periodically to charge the 12V, because the 12V is also used to update the remote control systems via the Bluelink app. My Bluelink app didn't tell me anything about the 12V battery when it happened to me. The dealership measured the 12V battery a few days later, they said that everything was fine. I actually never had this problem again afterwards.

[@crispynoges]

I’ve had this happen twice in 2 years with our e-Niro. As others have pointed out this is almost certainly a software fault as all batteries go flat it not being charged. The second time I bought a fancy jump start battery but it failed to fix the issue as its logic required some voltage to sense it was corrected correctly. The recovery man brought something similar which failed too - but his had an override button that fixed the issue. I was going again in only a minute or two. I so wish I’d noted the model of jump starter.

[@blobstrom]

Now it's done it once it will happen again I'm afraid as the 12v battery has been compromised, but you knew that already. Have to say my 2020 Soul in 1 year of ownership has never had any issues. Mainly it only gets driven on the weekends. I have one of them starter chargers in a door pocket ready for the day, but so far it's been used to keep my wife's phone charged and therefore connected to Facebook.. Also i use the Zappi scheduler to charge my car, never had much luck with my Leaf's built in charge timer and the Kia is just as complicated. Good luck, I'll be waiting for the video on Monday where the 12v failed again....

[@andybrown3715]

I have the Kona , had the same problem twice now, took it back to the dealer "Nothing wrong mate". So anyway I now keep the backup battery under the front seat now, but it shouldn't be necessary at all. Clearly there is a design/ software issue as there was now warning via the app.

[@mradford10]

Another great video from this channel. As I don’t own an EV I had no idea about the 12 volt battery nightmare. I’m so conflicted about EVs with their pros and cons. Watching you have to climb through to the boot and yank plastic covers off from under the bonnet doesn’t help, yet this honest and gritty delivery technique helps me process and prepare what I might be up for. How does battery management compare across brands? Can I assume Tesla owners don’t have the same problem as Hyundai owners or is this misguided? Thanks for sharing your lived experience - keep it up.

[@elmohead]

Tesla also has a 12v battery to run all the electronics.

[@LostInIce4]

I just returned my Nissan Leaf+ to the dealer due to many issues including dead 12v battery on many occasions. Just a small tip that I noticed with my Leaf. If the 12v battery is really drained you will need to leave the emergency charger plugged into the battery for a few minutes while the voltage is going up. I pick up my Ioniq 5 AWD Premium in 5 hours 16 minutes and 22 seconds. No, I'm not excited.

[@rkan2]

I still don't understand why the manufacturers don't just fully go away with the 12V battery. There is absolutely no need for it anymore.

[@williammillard687]

Totally agree...with all this amazing Lithium/Ion and LFP tech, it's almost inconceivable that we're still beholden to an old-style lead acid 12volt which can completely render the vehicle immobile! What??!!!

[@MYE19]

Tesla now use 12V Li-ion batteries. Apparently much better "reliability" and longevity.

[@williammillard687]

@@MYE19 it’s even taken Tesla almost a decade to ditch the 12volt lead acid battery....technology?

[@Joe-lb8qn]

I dont think the issue is really that it is old tech battery. A lithium battery could still go flat. The issue is, inability to monitor and manage the state of charge of that battery.

[@williammillard687]

@@Joe-lb8qn my main point is that any 12 volt battery (no real matter what it’s chemical type) could be allowed to drain flat effectively disabling the car, while the bigger battery is still charged or partly charged is unbelievable....yes, ultimately it’s an issue with the BMS, that it could happen seems crazy.... I had the 12 volt draining battery issue with my Birò.... eventually (after going through 3 ‘new’ ones!) we changed the wiring and ditched it completely.....the BMS seems to be capable of supplying the 12volts to the necessary bits and my phantom drain has miraculously disappeared! Hey ho🤓

[@Joe-lb8qn]

@@williammillard687 As you say its unbelievable (but unfortunately very believable) that such a simple function, to monitor the battery and top it up, isn't better implemented.

[@doesituk]

This is disappointing. Just swapped my Niro PHEV for the Ioniq 5. The Niro battery would go flat (below 9v) if you just left the a door open for a short time e.g. valeting the interior. It would then refuse to move even with a full HV battery weirdly coming up with "check brakes" as a fault message. Fortunately have one of those Artek jump starters like yours and agree they are great. It's under the boot floor at the moment. Will move it to the frunk tomorrow! Great tip, thanks.

[@davidbrown8733]

Hello Andrew - Its disappointing to see you having the same issue on this car too. I didn't buy your old booster after your issues with the E-Nero, but I have now used your referral link to buy this new one from Amazon. I've now taken the view that this is the "new" jump lead for EV's!!

[@MrEV]

You can buy a battery starter similar to the one I'm using here. I've not tested these though! Amazon UK: amzn.to/3tLIuo0 Amazon USA: amzn.to/3LakBNO And the battery monitor (which I'll show in a video soon) is here... Amazon UK: amzn.to/32XzTnT Amazon USA: amzn.to/3onhiJo (These are referral links - even if you buy another product from Amazon instead, you'll still be supporting the channel. THANK YOU!)

[@capitanocorelli1781]

Love to support your channel by purchasing from Amazon Canada.

[@LouDeVere]

Mate, I could almost dive into my computer screen and give you a big hug! I have a BYD Atto 3 here in Western Australia and have heard that there problems with the 12V lead acid battery used by BYD. This problem however is not limited to BYD as I've heard that Tesla, MG and now from your video, KIA have this problem too. Your video is absolutely invaluable to me. I'm just going on eBay and have found a Baseus unit which offers 3 different output currents so I'll just select the cheaper 8000 mAH version rather that the 20000 mAH version. Do you think that replacing the LA battery to a Lithium unit would be the answer to all of this? THANK YOU THANK YOU THANK YOU!!!!!

[@tonyhumphries8220]

I had a fully charged Kia Soul EV, and the 12v battery was dead. RAC man said a cell had gone, but KIA said it was fine-we shall see. Invested in jump start device like the one you use Andrew and the device you recommended to monitor battery condition. This failure was the first time in 50 years my car would not start! And they call it progress.

[@keepawayfromthetrout]

Nissan Leafs were supposed to have this problem and many folks experienced it but my leaf is over 6 years old now and I've (so far) never had a problem. I did get the version with the solar spoiler which trickle charges the 12v so I do wonder if that has helped. I have no idea if that is still working though it gets pretty grubby!! Think I better get ones of those jump starters just in case anyway they don't cost much now. Thanks for the reminder!

[@5kram]

Hi Andrew I have a 40kwh leaf I noticed the other month when my car was off and parked up not connected to the mains that it suddenly had a blue light flashing on the dash. It appears that the 12 volt battery is monitored and the main battery will keep it topped up if it gets too low in voltage. I think the first leaf used to have a little solar panel to keep the 12 volt topped up also but they have done away with these.

[@au18ert]

I've always used 12v optimizer when the cars not being used it just keeps it healthy. I had my ICE 12v 8 years before I sold it and it wasn't new when I bought it..

[@FHB71]

I had that with my classic Ioniq PHEV. The sensor in the trunk hatch was stuck and left the light on in the trunk. I quickly recognized that, because I had something similar with an Audi long time ago and the analysis cost me two weeks in the garage back in the days. I uncluttered the lock sensor and everything was fine except it did not charge, because - like here - the electronics runs on 12V. So I charged the battery for 15 minutes and then plugged the car into the charger, afterwards the drive battery charged up the 12V and everything was fine ... however 2 years later it turns out that the 12V was actually damaged by deeply draining it.

[@tomg8069]

I have toyota hybrid and have already 6year oryginal agm 12 battery, it is yuasa company made in japan. Hyundai didnt learn from previous ioniq gen....

[@dl393]

Andrew, we get our I5 next week on the 1st March - lucky us - so I've just ordered both the gadgets so we can keep on eye on the 12V and jump the car if needed. Thanks for the tip.

[@MrEV]

Congratulations! You’ll love it. Do make sure your dealer installs the latest (February) update though as it fixes some nasty bugs. Refuse to pick up the car if they don’t!

[@Kermit26297]

Ordered the jump starter from your link. Have a BMW i3 and many owners have also had 12V issues. Good idea to have this at the ready.

[@markymarkreviews]

Appalling and worrying. I have had no such problems in my P45…yet! 6,600 miles covered. Totally unacceptable state of affairs. Have never ever experienced 12v battery issues in any car I have owned. And I have always done fairly high mileages and kept my cars for longer than 3 years generally. (3 to 9 years). And my previous BMW i3 had no 12v battery issues after 60,000 miles. I am almost refusing to get the 12v jump starter as I should not NEED to! It is almost insulting to me. Don’t worry I am not having a go at you, but Hyundai/Kia. Thanks for the video and what to do. Utterly bizarre that it just seems to happen out of the blue and without warning. I have also heard other Ioniq5 owners having had a dealer software update but one of those owners had a flat battery the next day. MM

[@jhawkins2049]

I totally agree with you. I haven’t had a problem with either of the i3s cove owned. It’s absolutely appalling that after paying £45k or so for a brand new car you have to consider buying jump leads! The downside also is that the dealer and as such Hyundai don’t get to hear of half the problems.

[@ChrisdyMD]

The latest software updates, including the BMS update, do not solve the 12v battery problem. It is believed to be a faulty control module which is causing a permanent power drain, thus flattening the battery very quickly. It wouldn’t matter what battery you had, the fault would flatten whatever battery you fitted. My P45 model is going in to my dealer on Wed (9th) to hopefully get sorted out.

[@fatboy19831]

Good information thank you. I have not had a problem with my 3s 12 volt battery. It is now about 4 years old. This is about when the original 12 volt would fail on a ICE car. I wonder if it is covered under the Tesla 8 year 130000 mile drivetrain warranty.

[@renerens]

I had the same problem with my wife's EV6 having it for just 2 days, now I also bought a small battery charger that is in the armrest storage.

[@foolcellsorryfuelcellmirag4835]

Yeah had the same issue in my 2012 leaf. After 2 years the 12 volt failed. Garage where as much us as a chocolate watch. Eventually after complaining gave me a new one. The key here is to find what is draining the 12 volt. For me it was the radio I left it on. What you have here is nissan kia etc give you are crap 12 volt batteries that discharge to easily. The jump start is a must for all ev drivers. On the old leaf if you kept the charging plug overnight without charging would drain the 12volt. I think sandy munro mentioned that the 12 volt battery will be with us for a while. I'm on my 3rd 12 volt battery and by far the best was from Halford. It was the most expensive one but worth it.

[@Alex-tj1zo]

I own an Ioniq Classic 28kwh and I never had this issue because I have an option in the dashboard menu to top-up the 12V battery when runing low. I activated that as soon as I have bought the car and now it tells me at start-up that the 12V battery has been topped up over the period when the car was off. I think that other models from Hyundai/Kia should have it since they have similar or identical menu.

[@constructioneerful]

Yup same here. 28classic. It’s surprising that’s not a feature on the other Hyundai. I get a dashboard message from time to time that says the 12v has been topped up by the main battery.

[@constructioneerful]

Happened this morning !

[@Alex-tj1zo]

@@constructioneerful Then conidering the age of the batery, it could be time for a replacement maybe

[@5salive236]

No idea if this is the case in an EV but in the Gen 3 Prius opening any door (confirmed via Techstream software) boots up 24+ power hungry ECU'S and doing this over a prolonged period without first powering up the car (airing/cleaning/detailing etc) drains the 12v. Opening the drivers door adds to the drain by running the pump to pressurise the brake booster. It's worth noting that fully draining a 12v lead acid battery is reported to reduce it's capacity by up to 5% each time regardless of recharging to max.

[@uTPH1]

This happened to me with a Prius PHEV so not just BEVs. I had already bought a jump-starter as I was going to be leaving the car at Heathrow for 3 weeks and had previously had my cars jump-started by the valet parking folk after 2 long stays. I ow have a Kona (21 plate) which has a little light in the centre of the front emblem that shows the 12v is being topped up - I've actually only seen this on once so probably working, don'y know how often hence keeping the jump-starter.

[@johnkeepin7527]

Quite recently I came across the same story from an American guy with that model of Hyundai. Unfortunately that firm is not the only one with faults like that. Years ago, I (and thousands of others) had similar issues with the old Honda Civic Ctdi model, in which occasionally the 12v 70 Ah battery would discharge overnight, thus being unable to start the engine. It was caused by a software fault in a Bosch product, and as my car was under warranty it was repaired by the dealer with no specific charge. The method was to upgrade the firmware supplied by Bosch for the component that caused it. Like many modern cars, it used the Controller Area Network (CAN bus); ironically invented by Bosch, which is a complex system designed to use a two core cable for everything rather than a multi core, or lots of cables to perform a variety of functions. When the fault occurred, something did not switch off properly, and continued to draw current from the 12V battery. I happen to know some of the detail about that fault, as I know one of the (ex) workers at the Honda factory, who had to deal with it. No doubt they claimed back from Bosch (their supplier) after picking up the costs of fixing the fault with their customers, like me. Like yourself, I carry a similar jump start product. At present, I run a Toyota hybrid, which only uses the 12V battery (which is a small one under it’s back seat, and awkward to access) for 12V circuits when the power is off - the rest of the time it uses a dc - dc converter when the traction battery is live. It is not even used to start the engine - that is done using the high voltage dc via it’s triple inverters (for the 3 phase ac motor generator), there being no conventional dc starter motor.

[@MattMcIrvin]

With their hybrids Hyundai got rid of the lead-acid battery entirely and made the 12V system run off just a section of the Li-Ion battery, and made it possible to jump it from the main battery with some button combo--no external equipment necessary at all, as long as the main battery still had some juice. That actually came in handy when my Sonata was sitting idle awaiting repairs after an accident. It's surprising to me they haven't done something similar with this EV--I wonder if there is a specific technical reason.