An update on the above post -- with some good news...

I have an appointment at the dealer 23 October for my first scheduled service (they tell me it will be "A2"...but this is a topic for another thread after I pick up the car)
In addition to the service, I have a task on the service order for them to check the 12v battery because I haven't seen "charged" as a status since 6 October. Only "partially charged". Highly unusual.

Until tonight!

After sitting in my car (fully on) for about an hour in the garage fussing with my new Tidal subscription (which will be yet another thread), the HV battery state of charge went from 29% to 28%. Not unusual at all. After I got out of the car, I plugged in the charge cable as I was going to make another attempt at a long-ish (to 80%), slow-ish (11kw) charge on my home charger to see if it would make any difference with my 12v battery charge level. I started the charging and then immediately went to my MMe app to change the charge limit from 50% to 80%. It was at this point, I noted that the 12v battery level said "Charged". HAPPINESS!!!

I will remove the 12v battery check from the service order, as the dealer said I would be charged about €300 if the 12v battery check did not result in a warranty repair.

 

You’re the lucky one. My car sitting in storage with a trickle charger went completely dead. Nothing worked. Had to use special key to unlock car. Tried the start button and nothing. Put a 15 amp charger on and kept getting error messages. Called Mercedes and was told to call roadside assistance to have car flat bedded to dealership. Tow truck arrived in about an hour and mechanic tried to get car started. Put on a heavy duty jumper battery and electronics did go on but message said car not ready to start warning. Tried all sorts of things to get car to start (65% SOC) to no avail. Now, to get car out of garage and onto truck. After much trial and error got car into neutral and we pushed it out of garage but couldn’t make turn to line up with truck. Tried to slide the car with the hoist cable and got it a few feet further. Friend came over and the 3 of us were able to push car back and forth to get it lined up with truck. Hoisted it in truck and away he went. Dealer called today to say nothing works on car and it will be looked at tomorrow. Car had dropped so low mechanic couldn’t get his hydraulic jack under the car.
I’m curious to know why the 12 v battery ran down and would not accept a charge. App reports battery health as good. This is my second 12 v battery. The car is designed to charge itself from the high voltage battery while in storage. It did this fine last year when I had the car into storage. Not this year. Battery slowly discharged and would not charge by itself or with a charger on it. Waiting to hear from Mercedes as to the cause. Needless to say I am extremely disappointed in this car.
And oh by the way as the battery discharged I got several warnings on the app: battery critically low, window open(it was closed), brake fluid low(nope) and no internet connection.

 

This sounds like the 12V battery failed in the end rather than simply being discharged to too low a level. It is possible that there was a fault condition and the internal fusing was triggered, which would cause the battery to not accept a charge and show 0V. While it is possible to get pure lithium battery cells to manufacture battery packs, any lithium battery in a device or as a stand alone battery also contains safety circuitry and fuses to prevent issues with faults in cells and issues with shorting, charging, etc.

 

Wow! That's the worst 12v battery story I think I've read in this forum!
Hope you have good luck getting it sorted out at the dealer. Am interested to hear if they determined the root cause!

 

I reported in post #51 above that my 12v battery started showing "charged" in my Mercedes Me app again.
I received a MMe update on my phone today and noticed right after that that the Service>Battery section now only shows state of charge. It no longer shows battery health!
I have read online many cases of failing 12v batteries in EQ's that need to be replaced even though "battery health" showed as "good". It never occurred to me that the MB "Fix" to this problem would be to simply REMOVE the state of health indicator!

Has anyone else here experienced the loss of Battery Health information in MMe?

 

Car currently at dealer. Weren’t able to get to it yesterday. Awaiting a follow up call today.

 

Thru out all my 12 v issues the app has always reported the battery state of health as good. I haven’t got a recent update to the app. It still shows both battery health and state of charge. However I no longer have internet connection to the car so I don’t know if communication is happening between the car and the app. It was reporting low brake fluid and now reports fluid as normal.

 

Hi Scott, it happened to me when i switch between regions DE -> CZ and next day i have reverted back to CZ, took 1.5 week to appear again as good, but battery was ok, through the workshop menu it showed over 13, prob my case was different due to gdpr reset but yours sounds like update triggered a state reset to activate monitoring, needless to say i agree bad sw design rather than showing actual state (i.e. MONITORING, IN_USE etc...) with actual values, app just hiding it. BTW check if you have maintenance package in your spec, i heard some eq series has default have them which makes A2 free

 

I still have both statuses.

 

Thanks, eqe300CZ. No, I don't have the maint. package in my spec. I ordered my car about two days after it was launched here in Sweden in Dec 2022. They weren't ordering any incentives at that time. I was anxious to get the order in because at that point rapid inflation was showing no signs of abatement and I was crossing my fingers they could get all the components needed. I told them i would reject the car if it did not come with everything I ordered. In the end, it arrived as ordered, but inflation turned around, there was not a resounding market acceptance of the vehicle, prices plummeted and incentives skyrocketed. In retrospect I bought at precisely the worst possible time. Add to that, I BOUGHT. I did not lease. Anyway, I still absolutely love the car and it has not dealt me hardly any problems like I read about in this forum.

And you could be right about geographic boundaries. My "issue" of not seeing "charged" happened after a trip from Sweden>Denmark>Germany>France>4.5 months storage in France in an underground garage with no mobile connection>France>Germany>Denmark>Sweden.

I'm home in Sweden now and as of a few days ago, it's working like it used to -- showing "charged" most of the time.

 

Thanks for sharing. This is how mine used to look until yesterday. It will be interesting to see whether it remains or disappears for you!

 

My MMe app used to look like jcapotos' screen for 12v battery status. As of yesterday, it now looks like the screen shot below.

 

woah should be one of the first in Sweden! Also i am glad its holding up, hopefully many more years! I dont know why mb didnt defend their ground more loudly, it stayed in top 10 range in ev-database for years and still there, but i can not complain i bought used one (yeah got gremlins too, still i am on the buyer side, if you dont make your money work for you somewhere else i dont see leasing advantage

 

I have never leased, always bought new, but should have seriously considered leasing of the EQE at my stage in life as this might be the last car I own. Leasing provides the opportunity to walk away at a specific point, and/or to get newer technology as it is released. I am a tech junkie and would enjoy a new car after having this one for 3 or 4 years. Selling on the used-car market or doing trade-in has its challenges, risks, and frustrations. There is an excellent guide to leasing on this site. It all comes down to understanding the financial and you negotiation skills.

Also minimal worries about maintenance and 12v battery issues.

 

Just got a text from my dealer. They say they have no communication between the 12 v battery and the high volt battery. They are opening case with Mercedes engineers for next steps.
I have been getting wild readings on my Mercedes app thru out the day. 12 v battery back and forth between fully charged and critically low. No internet connection. Error message when try to charge the high voltage battery. SOC on hi voltage battery went from 66% to 34% without the car moving. Anyone else experience non communication between hi and low voltage batteries??

 

My 12v battery State-of-Health screen in the MMe app has returned.
It looks as in post 59 by jcapotos
I'm now on MMe version 1.62.0 (3006)

 

I left the state for six months, and it was driven two times for a total of 30 miles about halfway in that period. Prior to leaving, the 12V battery was replaced and was 30 days old. My main battery state of charge was about 80% when I left.

Upon returning, the 12V battery warnings came up again immediately. This is a 2022 EQS 450+ sedan, bought used in 2025. The dealer said MB might not pay for a second 12V battery so I took it to a different dealer. They replacded the 12V battery and I drive it regularly, no problems with the 2nd battery.

 

@Magnet138 There have been many reports of 12V battery failures with 2022 models that were in storage for extended periods. This is not supposed to happen. It seems that this failure was fixed in newer models, and it may only need a software update for yours. If you plan to leave it in storage again you have two options:
1. get you dealer to research and find the appropriate software update, and certify that if the 12V battery fails again while you are away that they will replace it for free
2. put the 12V battery on a trickle charger while you are away

You were lucky that there was enough charge in the battery to start the car and get it to the dealer. Worst case was a completely dead battery requiring the manual key from the smart remote to open the drivers side door, a boost to get the car started, and hope that it would then allow the car to be driven to the dealer. Not the end of the world, but highly inconvenient.

 

For 4-month Mercedes EQS storage:

• HV Battery: Charge to 50% , then leave unplugged .
  
• 12V Battery: No trickle charger needed . The car auto-maintains it from the HV battery.
  
• Final Step: Lock it and check via app occasionally (not too often).
  

That's it. Safe travels