DC Charging stopped, EV Fault Message, Now won't AC Charge either

[LBS]

Was DC Fast charging at a Shell ReCharge station that I had used with perfect results prior.

Started at 56% went up to 66% then it stopped. Check EV Warning popped up both in car and on Charger station screen. (I have set charging limit to 80% for DC and 90% for AC)

I did get a picture of a curious blurb that appeared in the infotainment screen and not the dashboard, which said under the heading of [Vehicle Diagnostics 07-13-2025]: "A routine check has been completed." for all the help that puzzling statement gave.

Unplugged and went straight home, no issues with starting or driving, everything other than the small orange triangle, seems normal.

Experimented with trying to AC charge it with the OEM Hyundai Level 1 EVSE. Port on the car initially lights up and the 3 green bars show as normal, but then plugging in the cable results in nothing, and the port switches back off after a minute as if there is no power going to it. The car shows no charging being done, no messages. The EVSE itself shows no fault symbols or indicators, but car symbol stays green instead of going to blue as when it does charge.

While DC charging, I was listening to the radio with the car in ACC mode. Could this have drained the 12V battery down enough to cause all this kerfuffle after only 10 minutes? I checked the battery at home when it would not accept ac charge, and it was at 12.38v

I have connected an appropriately safe SAE battery tender trickle charger to the battery to see if it changes anything once the voltage goes up a bit, but remain skeptical. ***EDIT: Still nothing with the 12v battery now being up to 12.7V***

As I've only had this car for about a month, so I am dreading this problem being anything other than a 12v battery that is on it's way out. Any ideas, folks?

 

[LBS]

UPDATE
-12v battery was down to 12.34v after all night on trickle charger. This is bizarre, as it initially went up to 12.7 after about 1/2 hour or so of charging.
-Hooked up Veepeak+ELM car scanner and it read trouble code: P1AA7(00) for both OBD-ll and BMS
-Cleared both codes*
-Car then reported no trouble after re-scanning
-Car charges normally again using level1 at least (for now?) but siiiigh.

*after poking about online trying to figure out how P1AA7 differed from P1AA6, but everything I found was vague and frankly not very helpful. Saw that many people had simply disconnected/reconnected the 12v and it went away, others cleared the code and it went away, others went to dealer with multiple varying results. I could not sort out how mine fits in that mess.

Given the 12v battery voltage should I go back to the place I bought the car and moan about a new battery? They did claim to have a warranty coverage included for such.

 

[LBS]

Update 2
(Sorry if I am spamming my own thread, but for the life of me I can't seem to find an Edit button anywhere on the screen after my first initial Thread Starter post)
Everything was going fine today until I stopped at a Park for a small hike. Came back to the car about an hour later and as soon as I started it up, the same giant Orange Check EV warning popped up and then went to the side as a smaller symbol.

The difference being this time, I am able to charge it via the level 1 as if there is no problem.

The 12v battery read 12.38 volts a minute after parking at home, from a 30 minute drive. Am I naïve to hope it's simply a giving up the ghost 12v battery?
One note: the 50A "Blower" and "Cooling Fan" relays are both scalding hot-too hot to touch, I am surprised they are not melting. Various other Tan coloured relay blocks nearby are warm, but not nuclear hot. All this is possibly quite normal, but I have no basis for reference.

 

[KiwiME]

If you have a gen-1 Kona be sure it had a BMS software update issued late 2023.

 

[LBS]

If you have a gen-1 Kona be sure it had a BMS software update issued late 2023.

Thanks again for your time, Kiwi! Apologies, I should have included in all my posts that I have a 2022 model Preferred Trim, Canadian. (or perhaps I will poke in the user settings and put it up to save me, if I forget to from now on.
I got it used from a Honda dealer about a month ago, and I did not really put a huge stock in their knowledge of Hyundai EV's, so I also went to the local Hyundai dealer the day of initial purchase, and had them do a VIN check for any and all relevant Recalls/Updates etc., and they assured me it was all up to date. Now, *how* it had been previously updated, I don't know, as I don't know it's history prior to the Honda dealer, bar it was a trade in from an individual.

 

[insightman]

I can't seem to find an Edit button

The Edit button goes away an hour or so after you post your message.

For some reason, after I click "POST REPLY," I always find problems with what I wrote--no matter how hard I try to imagine what I'll want to change after immediately re-reading what I posted.

 

[KiwiME]

If you plug in an OBD dongle like a Vgate iCar Pro or just about any other brand and install the "Car Scanner" app on your phone, with the car in "Ready" mode you can find a single page with CCC, CDC, CEC and CED, etc values listed. If you post that screenshot I can probably determine if a BMS update was done.

These are super-useful for other things so a worthwhile purchase.

The update was specifically to address DC charging issues. However, having said all that, it could also be a simple connection quality issue. It would be a good idea to check the pins for cleanliness. There are drains so you can squirt mild silicon-type cleaners in there, or even soapy water. The large pins have plastic lead-in caps that should be in place.

None of the other items regarding the 12V battery seem likely to have caused a problem but I'd highly recommend installing a BM2 monitor so you can verify the behaviour and learn how that all works.

 

[KiwiME]

For some reason, after I click "POST REPLY," I always find problems with what I wrote--no matter how hard I try to imagine what I'll want to change after immediately re-reading what I posted.

I think everybody does. That's why I like that most sites allow a short time before encumbering your post with an embarrassing "edited" tag.

 

[LBS]

Wow, thanks for all the info!
I had the car plugged in Level 1 and was charging successfully for about 3 hours, and then looked over to see it had stopped for no reason- (nowhere near the 90% limit I have applied)

I turned off power to the charging cable, waited a few minutes and turned it back on, it accepted power and started charging...for about 3 minutes, and then turned off again midcharge.

The Aux battery is at 12.34v

 

[KiwiME]

Your 12V battery voltage seems slightly low. Be aware that when the traction battery is supporting the 12V system the system voltage sits at 13.1 to 14.7V. During driving it dithers between those two values depending on the 12V load

That "support" mentioned above is present (a) during traction-battery charging, (b) whenever the car is in Ready mode or Utility mode or (c) during automatic scheduled 12V charging sessions every 4 hours while parked. Unique to Utility mode is that the voltage is held constantly at about 14.5 as it's intended for 12V use, such as while camping. You can leave it in Utility mode for hours without any issue, or even use that to charge the 12V battery. While traction-battery charging the voltage is typically 14.7 for the first 30 minutes then 13.1 until the session finishes. Right after that it drops back to the native unsupported battery voltage but shows spikes every 30 min while cell balancing takes place for some hours.

It's very easy to run down the 12V battery as many discover to their detriment by leaving a door open while they sit in the car reading the owner's manual. Just joking ... no one ever reads the owner's manual!

AC charging issues are easier to pin down as the process is simple. The AC outlet needs to be in good shape as any warming at the plug will cause the EVSE ('charger') to kick down the current, or switch off. Another thing is the ground connection at the outlet. It's not really the "earth" ground that matters but rather the bonding from neutral to earth ground, usually done in your circuit breaker box. The EVSE dribbles a tiny current (0.2 mA) from line to "earth" and expects that to remain steady while it's 'on', testing the continuity of that connection, so a flakey wire between receptacle and breaker box could cause issues.

You could wiggle the J1772 plug while charging to see if that's causes the flakiness.

 

[LBS]

A lot to digest...
I did discover that the outlet I was planning to use in the garage for level 1 caused the charging cable to refuse to work because of a ground fault (lack thereof, the previous owner was not an electrician by any stretch lol) so I am using a properly grounded outlet from my dining room which is about 4 feet away from my car. I have been using this with perfect results for the past month.
I am reluctant to believe that in conjunction with the DC charging failure, it now has suddenly started acting up at this exact time though.
The connection at the car is pristine clean and has zero apparent play or untoward look or appearance, but will investigate further, thanks!

*Edit (ha! caught it in time lol)

Also, since the first time today, it was just sitting by itself at the sidewalk while I was off on a hike, and it did the whole Check EV warning thing at start up, in that instance it had nothing to do with being possibly caused by faulty service connections or equipment whilst actively charging.

 

[KiwiME]

Oh, I missed your first mention of Check EV. That's a catch-all for any electrical issue and is more serious than an EVSE issue. If you have a warranty you need to take it into the dealer.

 

[LBS]

As you suspect, now so do I, drat! I poked about a wee bit, and the "Service Campaign 9A4: Kona EV DTC, BMS Update, and BSA Replacement-Dealer Best Practice"

Re: Code P1AA7- "Will require the Battery System Assembly to be replaced, and then the BMS update to be performed."

I'm trying to keep this firmly in the "First World Problem" mindset, but son of a....

 

[electriceddy]

As you suspect, now so do I, drat! I poked about a wee bit, and the "Service Campaign 9A4: Kona EV DTC, BMS Update, and BSA Replacement-Dealer Best Practice"

Re: Code P1AA7- "Will require the Battery System Assembly to be replaced, and then the BMS update to be performed."

I'm trying to keep this firmly in the "First World Problem" mindset, but son of a....

It will be a bit of a wait for the new warranty pack if it indeed requires replacement, but after that you will own a Kona EV with a brand new battery. Should be good for many years.
At least the problem showed itself early in ownership.

 

[LBS]

It will be a bit of a wait for the new warranty pack if it indeed requires replacement, but after that you will own a Kona EV with a brand new battery. Should be good for many years.
At least the problem showed itself early in ownership.

Thanks for the optimistic outlook passed along, appreciated!
It's funny, the first thing I did after driving it home on day one, was to inspect and replace the GRU oil, and was vaguely hopeful based on the look of the drained out stuff that I was set for at least a *little* while haha. So am a bit miffed that now this new unrelated issue has veered into my lane.

My previous car to this was a 2nd Gen 2009 Prius, so other than the Kona feeling a little bit cramped, I really do like the thing so far.

 

[KiwiME]

A check of cell balance with the OBD kit mentioned above might reveal more about the reason. There are 98 cell groups in series, each group with three cells in parallel. The voltage reading resolution is 0.02 V for the 98 groups.

 

[LBS]

I am afraid I am hilariously technologically challenged, so before I bollox it up trying to figure out the horrors of "upload a file", I can only say that I took a screen capture of one of the scanned info pages, which showed all of the 98 battery cells at exactly 3.94v, except for the Twins Weird Harold #43, and Weird Wanda # 47 who both had to be different at 3.82v each.

 

[KiwiME]

...except for the Twins Weird Harold #43, and Weird Wanda # 47 who both had to be different at 3.82v each.

Well, there's the problem. I had typed, then deleted, that 0.10 is the limit for cell imbalance but didn't want to jinx it. Now I'm certain you're getting a new battery. It's not a bad thing, my 2018 is still at 100% health due to a replacement late 2022. It had an imbalance of only 0.04 but that was persistent for four years.

 

[LBS]

"Well, there's yer problem, lady" hahaha

I can't say I'm looking forward to the process, but meh, luck of the draw. Thank you very much for your interaction.

 

[LBS]

Update for posterity if nothing else, I guess...

Dealership took a month to "try things" despite me telling them/showing them the pretty crystal clear info of a 30 second scan showing the detailed results of the battery being bad according to the car itself and their own parametres regarding the Trouble Code displayed. After their initial mucking about with the charging port (which did nothing as I knew it would, but merely resulted in the port socket not being able to lock in a cable anymore, which they will now also have to repair) they informed me that there were multiple other cars with a similar issue ahead of me, so it would take awhile to have a Hyundai Rep get to it.

One week. Two weeks. "It will be another week". Three weeks. "Oh, I meant another two weeks, not one week, sorry."
One month. "Yes, it's the battery."

When asked how long to repair: "Oh. Well. Anywhere from 2 months to 10 months. We had one wait for 10 months. Maybe you're interested in a trade in?"

So now I can't decide whether this is all worth it anymore. I had been vaguely worried about the GRU failures, but thought they had at least sorted the battery issues by the 2022 model year. That's the only reason I considered buying the thing.

Does it make sense to wait potentially almost a year, to get a new battery? Especially now knowing that the new battery will only have the remainder of the existing warranty period, and not another 8 years, which totally freaks me out! I've seen posts by owners with multiple new replacement batteries still failing.

:Unhappy mumbling and grumbling emoji: