12v battery critical
#1
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12v battery critical
I'm getting a warning message on my Mercedes Me Connect app that the 12v battery is critical. There is no warning inside the car and the car starts up just fine. That is for the regular battery in the car, right? Or is there another battery in the car that this is referring to? I see it's pretty simple to change the battery so should I just do that or could it just be a glitch in the app since I'm not seeing any warning in the car?
#2
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Originally Posted by LenniePaz
I'm getting a warning message on my Mercedes Me Connect app that the 12v battery is critical. There is no warning inside the car and the car starts up just fine. That is for the regular battery in the car, right? Or is there another battery in the car that this is referring to? I see it's pretty simple to change the battery so should I just do that or could it just be a glitch in the app since I'm not seeing any warning in the car?
I bought this tool to check battery and cranking power, easy to use.
How old is the battery?
My GLC is 2018 and this tool shows 63% battery is good.
ANCEL BA101 Professional 12V...
#3
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MY'14 W212 M276 3.5NA @60kMi
Low charge, what to do....
Now you are aware car keeps tab on its battery charge.
Low charge is No1 cause of electrical issues down the road.
How long does it takes to reach warning charge level:
4 days, 3 weeks, 1 months?
A CTEK float charger is a great option to prevent deep drains while parked.
Having a jump pack from Amazon in the trunk is good insurance you can always get engine started.
Low charge is No1 cause of electrical issues down the road.
How long does it takes to reach warning charge level:
4 days, 3 weeks, 1 months?
A CTEK float charger is a great option to prevent deep drains while parked.
Having a jump pack from Amazon in the trunk is good insurance you can always get engine started.
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Teckno (10-15-2023)
#4
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#6
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MY'14 W212 M276 3.5NA @60kMi
new battery ...?
Maybe now it's time for a fresh battery because that's exactly the first step dealer will take.
When this happens again next month it will be harder to point at another bad battery.
🤞
#7
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MY'14 W212 M276 3.5NA @60kMi
not random chaos...
Cant agree more for jump pack and charger.
This starter saved me a few times already and its a power bank which is also nice.
Here are my tools:
Car Jump Starter 2000A Peak... https://www.amazon.com/dp/B09N37C4LG...p_mob_ap_share
YONHAN Battery Charger 10-Amp 12V... https://www.amazon.com/dp/B097D397M6...p_mob_ap_share
This starter saved me a few times already and its a power bank which is also nice.
Here are my tools:
Car Jump Starter 2000A Peak... https://www.amazon.com/dp/B09N37C4LG...p_mob_ap_share
YONHAN Battery Charger 10-Amp 12V... https://www.amazon.com/dp/B097D397M6...p_mob_ap_share
Do you have a good scanner to read/reset faults of computer modules?
> LOW BATT. troubleshooting logic:
- High discharge rate while parked ?
- Low charge level while driving ?
- Old spent battery?
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#8
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I'm away on a fishing trip so I called my local mechanic. He ran over to the house, jumped it, and took it to his shop. He just called and he's putting a new battery in. $450 total with labor which includes picking the vehicle up and returning it. If I was home I could have done it myself and saved some money.
#9
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MY'14 W212 M276 3.5NA @60kMi
I'm away on a fishing trip so I called my local mechanic.
He ran over to the house, jumped it, and took it to his shop.
He just called and he's putting a new battery in. $450 total with labor which includes picking the vehicle up and returning it.
If I was home I could have done it myself and saved some money.
He ran over to the house, jumped it, and took it to his shop.
He just called and he's putting a new battery in. $450 total with labor which includes picking the vehicle up and returning it.
If I was home I could have done it myself and saved some money.
#10
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CaliBenzDriver (10-11-2023)
#11
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Originally Posted by CaliBenzDriver
Dan, you come to party well equipped
Do you have a good scanner to read/reset faults of computer modules?
> LOW BATT. troubleshooting logic:
Do you have a good scanner to read/reset faults of computer modules?
> LOW BATT. troubleshooting logic:
- High discharge rate while parked ?
- Low charge level while driving ?
- Old spent battery?
Thinkdiag OBD2 Scanner Bluetooth, All System Bidirectional scan Tool OE Level Diagnostic Tools with ECU Coding,15+ Service Functions All Software 1 Year Free fits for iPhone & Android https://a.co/d/6SXKmeN
Its subscription based, first year is included.
Im in process of configuring laptop with OpenPort and Xentry. Let see how far I can get with it. ))
#12
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CaliBenzDriver (10-12-2023)
#13
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It is a very good price. Question is if he did reset charge in ECU. According to doc below its essential.
Attachment 452196
Attachment 452196
#14
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this is a good question, not all scanners can update ECUs, especially on MB or BMW, they want you to buy their product and subscription, xentry is very expensive and not all mechanics buys them if they don't have enough business.
#15
Last year, I replaced 6 years old glc300 oem Agm battery with Costco Canada Energizer H7-AGM 850CCA for about US$230, because the Auto engine Stop at braking, was not working at that time.
#16
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#18
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Originally Posted by sn202020
I did not reset ECU for battery replacement. But engine auto stop started working right after the replacement. No issues.
I thought ita BS as all modern system talks to each other and adapts. But, MB wont tell use the true.
#20
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Here's what my GLC is doing at idle. No registration of the battery. I called my local Mercedes mechanic who's been working exclusively on Mercedes for 40 years. He said he's never registered a battery after he's replaced one and has never had a customer come back with any drained batteries. Maybe Mercedes is just being super **** by saying they need to be registered and there's the slightest chance it could overcharge the battery?
Last edited by LenniePaz; 10-16-2023 at 04:32 PM.
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Barbaris (02-02-2024)
#21
I have a GLC3002017 Base model. For others who want to replace the 12V battery here is what I went through last week.
Original battery had been weak for about a year (lasted 7+ years, including 2 years of not driving much in Covid) - giving me the "Stop vehicle, Leave Engine running" message on dash. My local non-dealer-Merc-specialist shop had confirmed that battery was about 65% life a year ago but it took me a while to change it. Car was still starting fine but I wanted to get rid of the annoying message that can't even be dismissed.
After research on this forum and internet, I bought a H6 for $170 + tax from Costco (850Ah) - original Merc batt was 800Ah. Hooked up car to the battery of another car to keep settings (that is what I thought I was doing - see below). Removed the dying battery and put in the Costco one. Disconnected the other battery. When I tried to start the car it gave me a bunch of errors related to power steering, told me that I had to go to a mechanic etc. etc. and would not start.
Finally, after trying various things with no luck and deciding to get it towed to the shop on Monday, out of frustration, I just disconnected the newly installed battery (removed negative). Left it alone for 2 min. Reconnected. Car started up with no issues. Has been running fine for 1 week+. Other than the seat belt tensioner setting and 1 or 2 other minor ones there were no other issues or settings that were lost.
I went to my local non-dealer Merc specialist shop and they told me that this model does not have anything to reset nor any training for the new battery to do nor any registration. However, they also recommended I call the Merc dealer, which I did. They also stated that this model does not have any counter to reset nor does it have hardware that stores changes to how the battery is charged as battery ages; hence nothing to reset here either.
So, in summary, effectively I took old battery out, put new one in. Nothing to train, configure nor reset.
Posting here because of all the contrary info on this topic on the internet and no clear direction.
Original battery had been weak for about a year (lasted 7+ years, including 2 years of not driving much in Covid) - giving me the "Stop vehicle, Leave Engine running" message on dash. My local non-dealer-Merc-specialist shop had confirmed that battery was about 65% life a year ago but it took me a while to change it. Car was still starting fine but I wanted to get rid of the annoying message that can't even be dismissed.
After research on this forum and internet, I bought a H6 for $170 + tax from Costco (850Ah) - original Merc batt was 800Ah. Hooked up car to the battery of another car to keep settings (that is what I thought I was doing - see below). Removed the dying battery and put in the Costco one. Disconnected the other battery. When I tried to start the car it gave me a bunch of errors related to power steering, told me that I had to go to a mechanic etc. etc. and would not start.
Finally, after trying various things with no luck and deciding to get it towed to the shop on Monday, out of frustration, I just disconnected the newly installed battery (removed negative). Left it alone for 2 min. Reconnected. Car started up with no issues. Has been running fine for 1 week+. Other than the seat belt tensioner setting and 1 or 2 other minor ones there were no other issues or settings that were lost.
I went to my local non-dealer Merc specialist shop and they told me that this model does not have anything to reset nor any training for the new battery to do nor any registration. However, they also recommended I call the Merc dealer, which I did. They also stated that this model does not have any counter to reset nor does it have hardware that stores changes to how the battery is charged as battery ages; hence nothing to reset here either.
So, in summary, effectively I took old battery out, put new one in. Nothing to train, configure nor reset.
Posting here because of all the contrary info on this topic on the internet and no clear direction.
#22
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I replaced the battery on my 2019 GLC300 about a year ago, and never did anything other than just removing the old one and connecting the new one. No settings were lost and everything seems normal to me over the past year. A Mercedes mechanic I know told me there's nothing to reset.
#24
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I replaced the battery on my 2019 GLC300 about a year ago, and never did anything other than just removing the old one and connecting the new one. No settings were lost and everything seems normal to me over the past year. A Mercedes mechanic I know told me there's nothing to reset.