Need Help 2010 Mercedes S550 Red Battery Not Charged Message
Have 2010 mercedes s 550 red battery not charged message in dash car came in and tesed battery and failed installed a new batteryand small aux battery at left side of dash both mercedes batteries still have message I did a complete scan of vehicle with star scan and seen no codes that would cause message checked cluster and front sam module this car does not have a battery module like older 221 mercedes I checked alternator and is charging is has a battery cuurent sensor one wire goes to sam and other to battery positive both wires are good
I was looking on alldata and it shows an additional battery located in the trunk. Did you check there yet? Alldata shows one under the hood, 1 in left side of dash and 1 in the trunk. 3 total. I am not 100 percent sure they all have all of them but its worth a look.
Can you check your alldata to see how many batteries a 2007 S550 have please?
Identifix shows 2......one under the hood...one under the back seat?
So far, I found the 2 you mentioned on the 2007 s550 but everyone keeps saying it's got 3 and the 3rd by the driver side dash but when I opened driver side dash, no battery there
Reset and initialize what I don’t see any options for this
Are you just trying to get rid of that red battery dash light at the moment?
This vehicle has a backup battery also, usually about $45 and very common to throw the battery light in the dash. I ran the VIN and included a diagram, it is #120 in the picture. Good Luck!
Changed back up battery already it’s in my help request
This model does not have battery in trunk in 2010 Mercedes re designed the 221 chassis and just one battery under hood and a small one left end of dash
What scanner are you using, it is not likely there are no codes. How many volts at the battery? You said the Alternator is charging, but how much compared to spec?
Yes please check back on voltage to the batteries after you get car running. Let see what the voltage is like
Using a xentry starscan have 14.1 at batteries
Did you do the Alternator test in Xentry? (Under ME control unit)
No but I will try that in the morning the message in cluster just says battery not charged like it’s not seeing the state of charge of battery
Hi John, I had a shop call me on one of these today. I our case there was a code in the battery management system. The light stayed on until the codes were cleared.
Had one with the same issue a few weeks ago. Replaced front SAM cleared codes everything was fine. Do you have any codes in front SAM?
I made a post about this on this forum, you should be able to find it easily. If the BNS is working and LIN wire from BNS to front SAM is good programming the cluster or front SAM will be the next step.
Thank u I seen that article I wasn’t sure if u were talking about replacing Sam or just reprogramming it
Xentry will only allow you to program the instrument cluster or the front SAM if an update is available. You will need to check if either of those controllers has revised software available and program each as needed. If neither has revised software available things become significantly more complicated.
I had the same problems, usually it's the alternator even if it's charging. It needs an original Mercedes component inside. The charging relay. It is no problem with any batteries or the charging but the red battery light will appear in the dash without it.
Thank u Brandon car is fixed updates software in front Sam module and message went out i Didn’t have a alternator problem just Sam module wasn’t seeing state of charge if the battery thank u for all your help
Not sure if number My xentry connects to Mercedes server and checks to see if there is update software and there was and let me program it
Alternator works on lin bus message if you disconnect the lin bus and don't get over 14.5vdc check for poor chassis ground away from battery ground. Most common is a arching ground chassis to drivetrain. If you do get specified voltage check for lin bus message in front sam actual values. Possible loss of lin bus message between front sam and alternator. Additionally check actual value voltage…