jclarson99

My 2003 E320 had a red Battery Malfunction code. I replaced the main battery (in the trunk(, but the the battery warning code continues to display. Can anyone explain how to clear the malfunction notice?
Thanks!

pinebaron

Did you check if your charging circuit is working? Easiest way is to measure battery voltage while vehicle is running; needs to be 13.8 volts or slightly higher. Your car may also show battery voltage in instrument display. For additional details, search for battery threads (including mine) in this forum

sosh

Could be the aux battery under the hood that is throwing the code. Have it checked and also did you check the main battery in the trunk under a load??

jclarson99

Do you check the voltage at the battery?

ohlord

warning might not be the battery at all.If it did not go out with a new battery installed you need to check your charging system. Alternator or Vr may be dead.
MB roadside is free and they will come out and check the charging system or you can check it with a multi meter.
If it is the charging system don't be driving it much since you will only be going on what the battery has stored up and once that is gone you are dead in the water

what's the warning?
Battery
Visit workshop or stop vehicle

velezeddie

I'm having the same problem, have you found any resolutions to this code?

Diesel Benz

Assuming you have tested both batteries being well charged, then try the aux battery relay.

veraunc

How do you know which battery without taking to shop? 2003 E320