Excino

Hello, new guy here. So i have this fault. Changed my main battery, fault still remains. No info online about this error? Any help?

cetialpha5

How old is the battery and what's the voltage on the battery? Sound like what it says it is, you may have a dead cell and the voltage is probably below 11 volts. Maybe be time for a new battery. You could also go to an auto parts store and get the battery load tested.

Excino

i already have a new battery installed. Issue remains.

cetialpha5

You didn't answer the question. What's the voltage? Even new batteries can have dead cells and sometimes the dead cells don't show up until you get it load tested.

kajtek1

That error coming with engine running is charging issue, not battery issue.
How old are alternator brushes?

Excino

No, that error only comes when i take the key out. when car is turned on no error, when i shut it off and take the key out it displays that error.

Excino

battery voltage when car is off 12,7v when its idling - 13,8v, when a little pit of gas applied - 14,1v

kajtek1

12.7V at idle is bad. Get at least new VR .

Excino

Read again. I said 12,7v when the car is off. 13,8v when idle.

cetialpha5

Is it really -30 Celsius where you're at? 12.7 seems high when it's that cold. Did you check it with a meter? I'd also get it load tested. Mine drops as low as 11.5 volts when it's at 20 degrees Fahrenheit. You normally get a low voltage message when it drops below 11 volts. which I could see happening at -30.

Excino

Tell me when i mentioned any ambient temp? Now its +4 celsius outside. What -30 are you talking about? I get this message when i unlock my car in the morning also all day when i open it after unlocking it.

cetialpha5

It's in the picture.

Excino

zoom in. It's -3

cetialpha5

Well I suggest you get it load tested. Your best case scenario is a bad battery. Otherwise it's going to take some trouble shooting to find the problem.

You should also measure the voltage with a meter when you get that error message.

Excino

ok.. its funny. First. This error popped up on the used battery i used for 2 years and it was used before, because i bought the car with it. I changed the battery couple days ago and issue remains. U say my new battery is bad?

cetialpha5

If you're lucky, then it's just the battery, new batteries also go bad if they're sitting on the shelf too long or you just picked a bad one. Otherwise you have some odd electrical problem that someone will need to actually troubleshoot.

I also find it hard to believe that you have a 12.7 reading when it's -3 outside and the battery is under load connected to the car. Check your connections.

Excino

I already said it 2 times. Battery itself not idling not loaded just outside the car is reading 12,7v. When idling its 13,8v. How can i be more clear about it?

cetialpha5

I asked for the voltage of the battery when it's connected to the car when you get that error message. You can easily get 12.7 volts with no load, but once loaded, the voltage will drop. You only find out about a bad cell when the battery is under load, which is why I keep suggesting to get it load tested.

Excino

When the car is off and the battery is hooked in it shows 12,7v. Car idling 13,8v with no load. Now i removed the battery and will charge it all night and more. One guy said you must charge new battery atleast 24hrs before installing, because u not know how long it was on shelf. So iam sticking with that advice. Tomorrow when i hook that battery up if theres no error, it means that the battety just needed a good punch of electricity. Thanks.

cetialpha5

I don't think you know what no load means. No load is when the battery is not connected to the car and has been at rest for a little while. If you check the voltage right when you disconnect the battery from the charger, it will be higher than if you wait a couple hours. The car always has some items on like the clock, alarm system, bluetooth, etc. Therefore when it's connected, it's under load. The battery is typically an 80-90 amp hour battery. You just need to charge it til it reaches 12.7 volts at 70 degrees. With a 10 amp charger on a dead battery, that should take a little more than 8-9 hours as you have line losses and it's not a direct 100% charge. Normally with a battery that's slightly discharged, it won't take nearly that long. Of course if you just have a 2 amp charger, it will take a lot longer. When I've connected a fully charged battery to the car, it read 12.3 volts and that was at 70 degrees. I get a reading as low as 11.5 volts when it's 20 degrees Fahrenheit outside. That's why when you claim it's 12.7 volts and the temperature is -3 C, I find it hard to believe. That's why I asked for the voltage of the battery when you got that message. Either it's below 11 volts and the car is fine, or if it's above 11 volts, you have some other issue with the car. Just basic trouble shooting 101. I still feel like you haven't really given me the answer yet.

Excino

Its not todays picture. I took it couple days ago. Now it surely reads 12,7v when the battery is just plugged in, car is off. And when i open the doors the fault is there udervoltage charge battery. I checked again, its 12,6v. Its about +3 outside right now.

cetialpha5

Is that the voltage in the display or did you check it with a meter? Anyway, sounds like you have some other more complex problem. You either need to dig up a wiring diagram to troubleshoot it or get it scanned and see if there are any MB specific error codes.

Excino

i checked with a meter.

Excino

quick update. I was charging the battery for about 6hrs. Plugged it in checked the voltage its 12,8v. Turned the car on, got some load. Displays 13,5v.

cetialpha5

When you get it load tested at an auto parts store, they put a 100-200 amp load on the battery and they see how well it recovers. If it passes the load test, then you have some other strange problem which you could try trouble shooting by getting the car scanned for MB specific trouble codes.