My GLC 300 4matic with AMG package was 2 days old/40 miles when it wouldn’t start. Error message referenced the battery system. MB roadside assistance got the car started and I returned it to the dealer. They still have my car almost a week later. I’m beginning to think this is a more protracted problem.

 

protracted

I dont like the sound of "protracted".. When I had 300 miles on it, the car would not start but after an hour it did.
I have given my car to the MB service center today and they will monitor it for 5 days. They are suspecting something is causing the battery to drain, they need to spot the culprit.

 

Had this happen on my 2022 GLC300 AWD. I was going to report it, but the car started up, and the message hasn’t shown up since then. I suspect the cars get started and driven only. Few minutes each time while they’re on the lot. That tends to draw down a battery, while normal driving tends to charge up the battery and keep it charged.

at any rate, if it happens again, it’s getting reported nd the get gets to spend some t8me at the dealer.

 

I’m having the same problem. My car was 4 days old. I took it in they said they repaired it and now here I am again 6 days later it happened again. A storm of computer messages mentioning the 12V battery and the car won’t start. Very frustrating!!

 

Same issue with my new 2023 GLC 300. ☹

 

I posted this on another thread here, for details.
My 2021 GLC300 awd was doing the same, it would drain for no reason. Now 4 visits and 2 new batteries. Warning has come on 4 times since last battery. Has not come on in a few months.(NOT weather dependent).

All they could come up with was “an internal battery fault”. Another visit for B service Friday, so we’ll see what the analysis says- I’m expecting nothing.

 

I purchased a 2023 GLC 300, and with 1300 miles the car died, maybe electrical. Two weeks in the service department and still no answers. This won’t work for me. Lemon, or is this the norm for new technology car? Help!

 

Had my B service last week. I reported the 4 battery alerts since last new battery. Diagnostics showed nothing abnormal but they replaced the battery ( original and now 3 replacements.) No deeper diagnostics that were promised 2 batteries ago.
No warnings last 3 months with 3rd battery and 4 th battery ok since installed 5 days ago.
I still think it’s a deeper electronic issue but they’ve been willing to put in new batteries, so I guess I’m good until/ unless it starts warning/ discharging again. They still say there are no technical alerts on the issue.
Did get to use an EQB as loaner.

 

Is it completely resolved for you now? Also, how do these loaners work? Is it covered by MB only or through your insurance?

 

[thank you all for sharing your experiences. My service provider is putting a new ESP Controle module . Hoping that will fix the battery draw.

 

same problem after 3 days of ownership. mine has been at the dealership for over a MONTH now

 

This is strange …my car is in the dealership for two weeks now .. they replaced ecp , now they say there is some communication issue through Ethernet

 

I have this issue in the first 3 days of purchasing new 23 300 4matic. Called dealer they said mostly like the issue is related to car being idle on the lot. I never had issues with starting the car. I saw the message in the app.
They asked me to drive for a day and see if it goes away. It was gone after that day & never seen again. Car is 2 months old now..

 

Just a thought on the draining batteries. Are any of you leaving the key fob in or near the car? If so it may cause a drain as the fob and the car are constantly communicating. I know that they go into "sleep" mode, but I've seen it happen on other cars. As I said, just a thought.

 

For info,

Just replaced the main battery on my July 2017 GLC250 4MATIC after getting the 'stop car, leave engine running' dash message. Believe the battery was original fit, so I got about 6 years before replacement. Never used the GLC START/STOP functionality.

Interestingly, the original battery was an Exide 70 AHr / 700 CCA. The battery compartment seems like it would accommodate the next size up battery being an 80 AHr / 800 CCA, which might be a better choice (and cheaper here in Australia). Charging voltage after an hours driving, and battery temp at about 20C, settles to 14.4V measured on the dash 'Vehicle data'.

 

GLC 2023 300 same issue, took to the dealer, they charged the 12 v battery and again seeing the problem after a week

 

[thank you all for sharing your experiences. My service provider is putting a new ESP Controle module . Hoping that will fix the battery draw.

Did this resolve the issue ?

 

Likewise for me. Picked up car less than 2 weeks ago. Four days after picking it up, had first low battery message, then again 10 days after we got a "battery critically low" message. We took it to the dealership. They checked the battery and said it tested okay on their system so they did a charge on the battery (yesterday). We will see how it goes from here. Yes, very disappointing for a car that is so wonderful otherwise.

 

Brand new 2023 GLC 300 bought a week back having the same issue. Getting a 'Battery critically low' message. Very disappointing

 

I have a 2018 250d GLC with a similar battery draw off problem. If the car isn’t used for two days I get a message on the app and the car saying the charge on the 12v battery is at critical level. No one - including main dealer - seems to know what’s causing this. Has anybody had a similar issue resolved?

 

Picked up my ordered 2023 GLC about six weeks ago. Put 3000 miles on it with no problems whatsoever. Then it sat in my garage for about three weeks (I was out of town). A few days ago I received an automatically generated email from Mercedes Me Connect telling me my battery charge status was “critical” and to drive the car for 30 to 60 minutes or connect a battery charger. So I drove it. Everything OK. Looking into this I discovered that the car is using it’s 12 V battery just by sitting, whether on the dealer’s lot or in your garage. Maybe it is connected to online services, alarm system, 360 degree feature or whatever. A low battery can cause all kinds of problems. If you know the car is going to sit for ”extended periods of non-operation” (Mercedes manual) you should turn on the “standby mode” found in the multimedia system under settings>vehicle>open/close. This is reviewed on page 190 in the 2023 GLC manual. Also, it will tell you how many weeks it is good for when you turn this on. Do this only when you have a full/normal charge level to start with. Hope this helps.

 

Wow Same thing here too. Day before yesterday, I got a weird message from Mercedes about the 12 V battery. I ignored it today. I wanted to start my car. There is 12 V amber flash in the car. Car totally dead now ; registered for roadside assistance. Took 35 minutes and he says to wait for 60 to 90 minutes. This is not the way. I wanted this day to go to go frustrating. Thanks for the info. Thanks for the info. at least I know the reason now, good weekend.

 

I dont like the sound of "protracted".. When I had 300 miles on it, the car would not start but after an hour it did. I have given my car to the MB service center today and they will monitor it for 5 days. They are suspecting something is causing the battery to drain, they need to spot the culprit.

If it has the 48 volt battery then they are effected by the auxiliary coolant pump running on long after the engine is stopped. Mercedes know about & a software fix is on the way. The temporary fix is lock the car as normal, leave it for 20 minutes then unlock & relock without opening any doors etc. This apparently interrupts the pump run sequence.

 

We had the same issue. We now know that the car is constantly searching for the key fob and this is draining the battery. So at home in the garage, we don’t lock the car. And the battery would be drained. The dealership told us to keep it locked anytime we aren’t in the car. Seems to be better now. 🤷

 

Do you hang keys in garage? It being close may cause contact between the 2. Just a thought.

 

Going on 4 days now with no issues. No messages, nothing even implying that I have a weak or dying battery. My battery was never drained. Well to be clear neither battery was drained. I had a 16 module software update performed.
It appears that there are GLC updates to solve these controller module issues. That is all the info that I could get.
So we will see if that has fixed the issue. I sometimes lock the car in the garage, but most of the time I don't. I definitely don't want to worry about an unlocked car draining my battery, that to me would be a major defect on the manufacturers car.
If that is the issue with your car, I would definitely get that fixed from the dealership. I would not take no for an answer. Just my two cents. Thanks for the feedback.

 

Either MB updated their software or maybe the car is getting to know you
But similarly, I usually don’t lock it in the garage unless I rub by the handle with the fob in my pocket. There were times when it said “partially charged” but I ignore it.

 

One week into my new car ownership I got a 12 volt week battery message. I ignored it and just drove the car like it said on the message. All was fine for about a week, that's when I was left stranded. Stranded. And that is when I received multiple warning messages. . Took it to the dealership. They did an ignition module update, 2 weeks later it happened again, and the car at that point had 600 mi on it. I was starting to get a little uneasy with the reliability and being left stranded with family and friends. I made that clear to the manufacturer via phone call and also to the dealership. The dealerships have to follow what the manufacturer suggests as part of their troubleshooting process. But hopefully you won't have that problem and just driving your car for a good distance. Will charge everything up. The 12 volt battery is in the rear next to the spare tire and the lithium battery is underneath the cabin filter. That is a 48 volt lithium cell and will fry you! Good luck

 

Did this solve the issue ?

 

On my previous post I had the ignition module software updated. That is what the manufacturer told the dealership to do. The dealership has to follow what the manufacturer says. 14 days later I had the same errors of multiple warnings and car left me stranded. Luckily I was at home on Christmas Day. Back to the dealership, another phone call to the manufacturer to document all of these issues. Three days later and 16 module software updates were performed. To date January 13th 2024 it has been running flawlessly. But it always ran very well. It's the starting; that was the main issue, with that underlying thought in my head. Is it going to start this time!
If you don't mind sharing the manufacturers date. It is located on the driver's side door jam. Mine is manufacture of 9/23.
I did read in one of my very deep dives into this issue that there was a batch of later. 23s that had software issues from the manufacturer. Hope this helps.