ours does that. esp if left sitting for a while

 

Thanks, it seemed odd, but if it's consistent, I'll ignore it. It was sitting for a while both previous times too.

 

The car seems to reset to default AC settings, MPG tracking, etc. This is the third time it's done it.

Not sure what's going on, does anyone else have a clue?

Mine (2022 hybrid) has done this a couple of times since I got it in April, but the problem hasn't happened in the last 2 months (did I just curse myself??). I had mentioned it to the dealer and he told me to come back if it ever happens again, that there is a small battery which might need replacing (sounds like BS to me)

 

I agree, that sounds mighty strange to have a separate battery to hold the data, but it if keeps up I'll bring it to the dealer to have it looked at. {edit} I realize it also loses the console setting. It forgets I picked the MPH for the center and indeed forgets I even have it as a choice. Definitely not right. {/edit}

 

Unfortunately, this seems to be 'normal' behaviour if you leave the car sitting for about a day or two. It happens all the time with my 2022 Hybrid. Centre instrument cluster will reset to the default screen, some settings will be lost (but not all, which is strange), and your climate control will be off.

For my settings, I've noticed things like number of times the light blinks to be remembered, but something like the wireless charging pad option to reset (I keep it off, since I don't have a phone capable of wireless charging, but the setting always goes back to 'on' when my car settings reset).

 

I also have it occasionally happen on my 2022. It's not due to sitting. I can go to work with everything normal, but when I go home, it has reset a few things. Sometimes it will happen twice in a week. So far, it has been several months.

 

This last reset had the AC off and at 72 when I hit the fan button, but returned to 74 by itself. ??? I lost my center console choice and it was not selected as part of my cycle of items. But it did remember I was playing the media device and the song it was on, and where in the song it was stopped. It zeroed out my MPG (which is the most annoying actually as I'd like to know what my cumulative MPG is on this new car.) As far as I can tell, that's all that reset. I wonder if a flash of the system will stop these issues?

 

The car seems to reset to default AC settings, MPG tracking, etc. This is the third time it's done it.

Not sure what's going on, does anyone else have a clue?

My 2022 Tucson Hybrid Limited has done this multiple times. At first, it seemed like it was only after sitting a week on vacation. But now it has happened overnight several times. The most annoying part is the mpg reset, but I guess the AC default temp and the center driver display (which I normally set to highway speed) also defaults to something else.

I complained to the dealer at the time it was only happening after a week shutdown and they claimed it was normal.
Now that it is happening more often I am inclined to bring it up again. I worry that the system is resetting as though the battery is being disconnected, but I am not sure if that would produce the same symptoms. I am hoping raising the awareness of the issue here on this forum will get a response from Hyundai.

 

It appears to be a defect in newer hybrids. As Andy Ross mentions above, perhaps the 12V system is getting insufficiently charged. The car does complain rather quickly about a drained battery in accessory mode telling me to start the car. I'm talking about less than a minute. That could be fixed with an update to the software. It's a significant annoyance that eliminates the value of overall MPG average. Perhaps a plan as mine doesn't get near 50. 🤷‍♂️

 

From what I know, the Hyundai hybrids have a Li-ion battery for 12V and it somehow is charged from the HV pack or charging system. There is probably no traditional alternator. I wonder if it sometimes is allowed to drain down a bit too much before it decides to charge it back up, causing some loss of settings.

 

The dashboard state of charge indicator never goes below 1/4 or above 3/4. The manual kind of implies that it protects the system from going below 12v. But I rarely see it down that low even when parking, but I suppose I could keep an eye on it at shutdown to see if that correlates to the zeroing of the MPG.

 

From what I understand in the hybrid cars, there is no traditional alternator to start the engine. The 12V LiPo accessory battery is used to control and start the car, which is why if you let it drain (e.g. leave cabin lights on, leave radio playing, etc), then you won't be able to unlock your power locks nor start your car unless you use the interior 12V jump start button. Once this is pressed, it jumps the 12V accessory batter from the main hybrid battery.

My understanding is that the dashboard state of charge indicator is for the hybrid drive battery, so it makes sense it never goes below 1/4 or above 3/4. I don't think there is any indicator for the accessory battery.

 

From what I understand in the hybrid cars, there is no traditional alternator to start the engine. The 12V LiPo accessory battery is used to control and start the car, which is why if you let it drain (e.g. leave cabin lights on, leave radio playing, etc), then you won't be able to unlock your power locks nor start your car unless you use the interior 12V jump start button. Once this is pressed, it jumps the 12V accessory batter from the main hybrid battery.

My understanding is that the dashboard state of charge indicator is for the hybrid drive battery, so it makes sense it never goes below 1/4 or above 3/4. I don't think there is any indicator for the accessory battery.

I don't think this relates to the issue of the system losing its state. In no case where the state was lost have I left the lights on, the radio playing, or used any accessory feature. The system was shut down for the night, started up the next day and the system state was lost. This seems to be an issue many of the Hyundai hybrids have in common. It may have to do with the 12 V system, but why a really minor trickle of power for maintaining a status would be enough to drain the 12 V system is either a major design flaw or Hyundai has a system flaw in how they maintain the state. It does not seem to be an easily repeatable error as it occurs randomly.

 

I have had it happen during the winter when the HV can often be up to 90% due to the engine running for heat and short drives.

 

Update: This keeps happening, it's a minor annoyance, but an annoyance. If it happens to your hybrid, I'm asking you to report it to Hyundai so they fix it. I have done so and there seems to be no fix at the moment.

 

What would you suggest as a means of "reporting it to Hyundai"? For a different issue (Android Auto problem), my dealer sent me on a wild goose chase.

 

Contact Us | MyHyundai (hyundaiusa.com)

There is probably a similar owner's link in Canada. I used this before and got a response in 24 hours. I also called the dealer, but as you said...

 

For the last several times I've used my car, it has not done this. Perhaps as @steverino42 said about his car, it stops after a while. Maybe the 12V accessory battery needs time to fully charge up? Who knows, but I'm hoping I'm done with this issue.

 

And it's back, now it's almost every time I use the car. I have yet to hear back from Hyundai about it. I contacted them about something else and heard back in 48 hours, this has been a long time. Not encouraging.

 

I did hear back from Hyundai, they said to contact the dealer, oops...ugh.

 

It's a common problem, apparently. A lot of 2021 - 2023 models experience it, and people seem to think it's due to the 12V battery either running down, or Hyundai has programmed in a "too safe" low voltage cutoff.

 

Is it only the hybrid model that is affected?

 

It appears that way.

 

For what it is worth, I just sent a rather long email to Hyundai asking when they are going to fix this. This should be part of the extended battery warranty I purchased if not covered by the original warranty.

 

I've had the same issue with my 22 hybrid ultimate (limited). It was happening nearly every time the car sat for more than ~12 hours. After reading about the possibility of it being a conservative voltage cutoff I tried turning the park mode recording on my dashcam off. after doing this I haven't had the issue again, even when leaving the car for a whole weekend. this seems to indicate it has something to do with a low voltage cutoff.

Interestingly even when the display would be reset in the morning, the dashcam would still be powered despite having selected the most conservative option for the camera's voltage cutoff.

 

I don't have a dashcam yet (looking at getting one), so I am not sure whatelse it could be.

 

It's ridiculous that it happens at all and so consistently. It's a circular firing squad with Hyundai and the dealer. No one is willing to say what it is.

 

I have a dashcam which records even when the car is parked (e.g. will drain the battery) - however, I have already set the voltage cutoff to the highest (12.4V), and the car still occasionally 'resets', usually after a long weekend. Climate control will be off, (speedometer) dash goes back to the main default screen, etc.

Definitely an annoyance.

 

Yup, that's it. I would twitch each time I got into my car to start it. Now I have to decide if I want to move my music to my phone and just play via that, though the sound is not as good. Bluetooth sucks for audio, well, just sucks, but that's another story.

 

Unfortunately, this seems to be 'normal' behaviour if you leave the car sitting for about a day or two. It happens all the time with my 2022 Hybrid. Centre instrument cluster will reset to the default screen, some settings will be lost (but not all, which is strange), and your climate control will be off. For my settings, I've noticed things like number of times the light blinks to be remembered, but something like the wireless charging pad option to reset (I keep it off, since I don't have a phone capable of wireless charging, but the setting always goes back to 'on' when my car settings reset).

I'm experiencing the same issue with my 2021 Sonata hybrid. Very frustrating! I took it to the dealership but they didn't know how to fix it.

 

I think Hyundai knows what the problem is and it is too expensive to fix it for all our cars. The dealer "doesn't know" and Hyundai says take it to the dealer. My dealer is useless anyway. I'm hoping when I move out of Florida I find one that actually cares about their customers. I brought my car in for the recall and they asked if there was anything else, I showed them a code it was throwing ever month or so and mentioned this problem again. I got the car back and they only did the recall. No mention of anything else. Yesterday when I got into the car it told me "Service in 29 days."

I'll never buy another Hyundai or recommend one to anyone.

 

I turned off the charge pad for phones and the car hasn't reset since then. I don't know if that's it or not, but it's suspicious that the issue goes away after I make that change.

 

Hey joe, I know you've dealt with this a while as have I. Do you have the problem now that it's been a few weeks? I've also made little tweaks where the resets didn't happen and then did again.

 

I think I might have stumbled upon the source of the problem.

I recently sold my Mazda... and therefore, no longer carry the Mazda smart key/transponder. Since that time, my Hyundai Hybrid has not gotten "amnesia".

So, it's possible that the problem is somehow related to having a "foreign" transponder with you along with your Hyundai transponder.

Obviously, we need more testing... and I'm not sure that "correlation = causation"

 

I think I might have stumbled upon the source of the problem.

So, it's possible that the problem is somehow related to having a "foreign" transponder with you along with your Hyundai transponder.

Obviously, we need more testing... and I'm not sure that "correlation = causation"

Well, dang it... the problem did NOT go away. So, I was wrong about this having something to do with a foreign transponder

 

Someone mentioned ages ago that turning off the wireless charging pad helps with this. Maybe try that first?

 

I haven't looked here in ages. I did turn that off, it helped and not it only happens 1/3 as often. It still happens. I changed my mpg display to show cumulative and most recent trip, thus that no longer shows up as 0.00 when this happens. I've also become expert at resetting the dash and it's just a press of a button to put the HVAC on. But if this is happening, what else happens that I can't see?