If you've had a dead 12v battery please respond

[mikeselectricstuff]

There is. Sometimes it doesn't seem to work.

And it probably only gets enabled once teh car is in sleep mode - the issue looks like the car not going into sleep mode

 

[drivingbythesun]

Yes I will invest in one of these before a long trip, or something similar.
Quick question, when you "jumped" the 12 V battery did you apply the negative lead to the battery post or chassis ground as displayed in the owners manual on page 6-5?

I did red to positive black to negative. I did not have the manual with me, but I phoned a friend LOL and he said black to negative was fine.

Linda

 

[drivingbythesun]

You would think that there would be a battery management system in place that would charge the 12-Volt battery from the main battery on demand when it reaches a certain depletion level.

I checked both times this happened and it was already enabled both times. So yes, this is not a reliable system, or faulty.

 

[drivingbythesun]

I had this happen once; for a few days beforehand, I noticed that BlueLink was unable to get service, and the cellular modem reported its IMEI as all zeroes; I figured rebooting the car would resolve it, but normal restarts didn't. I was about to make a service appointment when the battery died overnight; a jump revived it, and conveniently fully rebooted the system such that the modem reported a real IMEI and was able to connect. It's purely speculation, but I'm slightly suspicious the battery was run down by the car attempting to find cell service; certainly that's one of the quickest ways to run down a phone battery, and while I'd be a bit surprised it would actually manage to drain the car battery, it seems plausible at least.

So I don't know about cell service, but I just was looking through my blue link app and noticed that it shows the last few requests sent. And there was one sent the morning of my 2nd dead battery, and it says "error". So perhaps that did have something to do with it. I'm buying one of those cigarette lighter things that show battery voltage and I'm going to keep an eye on it.

Linda

 

[Toolworker]

Thanks for everyone who's keeping this thread short. It's helpful to have this poll and list of failures without having to read a lot of discussion.

I've had a dead battery several times on my three month old Kona EV, and documented it pretty thoroughly. In my case, the car is refusing to run the Auto Battery Saver function when plugged into an EVSE, and on a few occasions it did that in a way that drained the 12v battery. There's a graph here and a video a few posts down.

After the first time, when Hyundai sent the AAA to "jump start" it, I bought a $70 lithium battery jumper pack and now consider it a minor inconvenience. Once all this virus stuff is under control, I'll see if the dealer can get it fixed, but it's not worth driving an hour to the dealer, leaving the car, getting a rental, etc., when I know I can jump it in two minutes. Meanwhile, I leave it unplugged unless I need to charge.

 

[Wildeyed]

Your poll fails to reflect another option: "my battery was dead and it was the car's fault". It's what happened to me. Hybrid Control Unit replaced under warranty 8 months after purchase. Off the road for 1 month. It's been fine since. Knock wood.

 

[Geoff Marshall]

Just found this poll. That's a large percentage of respondents experiencing a dead 12V battery!

I am on 4th 12V battery. I call the dealer and say 'I need another one' and they call when it's in. All under warranty.

On Friday, I get the 356V battery replaced and they said new firmware may solve the 12V problem. Fingers crossed.

 

[electriceddy]

Just found this poll. That's a large percentage of respondents experiencing a dead 12V battery!

I am on 4th 12V battery. I call the dealer and say 'I need another one' and they call when it's in. All under warranty.

On Friday, I get the 356V battery replaced and they said new firmware may solve the 12V problem. Fingers crossed.

New setting may indeed solve your 12 V charging issue, especially if a lot of short trips. Look for VCULDC C00D0111 software upgrade
Congrats on the new pack replacement

 

[Devhead]

Just found this poll. That's a large percentage of respondents experiencing a dead 12V battery!

I am on 4th 12V battery. I call the dealer and say 'I need another one' and they call when it's in. All under warranty.

On Friday, I get the 356V battery replaced and they said new firmware may solve the 12V problem. Fingers crossed.

Don't count on it. Mine got worse after the traction battery was replaced. Although, it is possible that the 12v battery had degraded so severely that the timing could be coincidence. Either way it was a frustrating few months.

 

[Toolworker]

Just found this poll. That's a large percentage of respondents experiencing a dead 12V battery!

A higher percentage of those with the problem will respond. But still.

... they said new firmware may solve the 12V problem. Fingers crossed.

Please post the firmware upgrade number(s) from your service order.

My 2021 was built in late 2020, but the service advisor says there are no updates outstanding. I can't believe that.

Look for VCULDC C00D0111 software upgrade

Anyone know if there is a U.S. equivalent, or is it the same?

 

[NRH]

Happened once, after a very cold night, while it was charging (L2). Jumped it, and then it was fine. No other problems in 2 years.

I'm not sure if we had a door open, perhaps? Hasn't happened in the 2 months since, so I'm not worrying about it.

One thing I noticed is that unlike an ICE car, while can be disconnected from the jump pack as soon as the engine is started, I needed to leave the jump pack attached to the battery longer, until the car had a chance to charge the 12v battery from the traction battery. I'm not sure how long it took, but I left it hooked up for an hour, while "running".

 

[HepKona]

Had to get jumped for a dead 12v yesterday. Every light was blinking, ABS triggering when I touched break trying to start it, beeps and clicking noises all over the damn place.

How ling till I can expect it to crap out again?

 

[OzKona]

How long is a piece of string? Lead acid 12V batteries don't like being discharged to that extent, and when it happens there is usually a penalty in terms of performance and battery life. One such event is surviveable but each subsequent event will take a toll. If this is the first time you'll probably be ok, but it would be a good idea to get a small lithium jumper pack which will get you going if it happens again.

 

[Devhead]

Had to get jumped for a dead 12v yesterday. Every light was blinking, ABS triggering when I touched break trying to start it, beeps and clicking noises all over the damn place.

How ling till I can expect it to crap out again?

Hard to say when it will happen again, just expect it to happen more often and it will get progressively worse each time it happens.

 

[apu]

Just found this poll. That's a large percentage of respondents experiencing a dead 12V battery!

I am on 4th 12V battery. I call the dealer and say 'I need another one' and they call when it's in. All under warranty.

On Friday, I get the 356V battery replaced and they said new firmware may solve the 12V problem. Fingers crossed.

Wow 4 batteries, that is impressive. I have been on battery # 2 now for almost 20 months. The new charging regime seems helpful. I am not expecting 5 years for EV service but 3 years would be nice.
Weird that Hyundai is obviously still having issues with dying batteries in the new Ioniq 5.

 

[George Davidson]

It happened to me twice. Had to pay for replacement on both occasions as it was over 2 years / the specific km.

 

[pulone]

I see there is a long thread already on the dead 12v battery, and I will go through that next, but I wanted to get this post out there ASAP.

My car is at the dealer right now for the second time for a dead 12v battery. Jumped by AAA the first time, checked by Hyundai, no problems. 2000 miles later, dead again, jumped by me the second time. They have had the car since Saturday and can't find anything wrong and can't replicate this issue. I get it back tomorrow morning, and if this happens again, it's getting towed back to them.

I want to go back to them with knowledge about how many people are having this exact problem to show them that it's not just me (and it's not because a deer ran into the side of my car either like they've hinted at). If you are willing to give me your name and e-mail address in case I take this further to Hyundai customer care please PM me that information and I promise I won't do anything with it unless Hyundai asks for it. If you just want to raise your hand here and said it's happened to you, I'll just count you in my non-scientific poll. And if this has happened more than once, I certainly want to talk to you. And everyone - Amazon overnighted me (like ordered 6 pm, on my door step 6 am the next morning) a power pack (the NOCO GB40 works great!). You might want to invest in one as it seems this is not a rare thing! I'm posting this on a few places so you might see this more than once.

Thanks for any responses!

Linda

My car started dying, about once or twice a week. on 2nd visit to dealer, they hooked it up to some machine that tested it over night....they said battery tested OK....I said it's not....turns out, their over night battery/drain tester was defective. They installed new battery and problem solved. Car 2019 Ultimate, battery was about 2 yrs old.........no charge/proration for new battery

 

[DavidR]

On 2019 Kona EV bought new on Dec 31 2020 -- Three times the 12v battery has gone "dead", and jumping re-started it. After my friend with his 2019 Kona EV called me to jump his dead 12v battery, we went to NAPA and both bought small Vector 800a lithium jump starter (& USB powerbank) units, and have both used them to jump our Konas since. Oct 25 2021 I got a new 12v Interstate 26R battery at the Hyundai dealer under warranty (which the dealer just slapped a Hyundai sticker on the side of) at 7321 miles.
WINTER STORAGE: Have stored Kona from Nov 23 2021 to present in unheated & unelectrified garage, disconnecting 12v negative cable (against advice to remove battery to inside storage) and with driving battery at 82%. Hyundai dealer and manual (p. 7-22) recommended inside storage of 12v battery and charging driving battery to 100% (p. H-5), but I only charged big battery to just over 80% since that was the advice re:fire hazard until replacement battery is installed. In 4 months of storage at winter temperatures (Ithaca, NY), new 12v battery with no trickle charge has degraded to 12.20v from 12.70v but big battery is still at 81%. Just got word from dealer that my big battery is scheduled to be replaced in a couple weeks.

 

[KiwiME]

That's useful info for cold storage since the question comes up often.
As an aside I lived in Ithaca for four years in the mid-1960s so I have a rough memory of the cold. My dad was in Cornell's astronomy department.

 

[rpark]

Are the problem 12v batteries lead (Pb) or a calcium/lead acid? The reason I ask is the 1980 GM cars came with the calcium/lead and they would not work in cold Canadian weather. They ALL had to be changed to lead to get them to start in winter.

I have lead (Pb) as my 12v battery in my 2022 Kona electric so at least it will work in cold Canadian winters.