The following procedure is a simple method to check if your Mercedes-Benz alternator is charging or check if the battery is discharged.
- Unlock the vehicle and go to the driver's seat.
- Remove the push start button by pulling it out.
- Insert the key into the ignition and turn it one click.
- Use the steering wheel buttons to show the miles on the cluster.
- Press the phone button and after 1 second, press the ok button and hold them both for five seconds.
- Select Vehicle Data on the cluster by pressing the ok button on the steering wheel.
- The cluster will show the Battery's Voltage and Current.
- Start the vehicle and you will notice that the voltage will go up and the negative current turns to positive indicating that the current is going to the battery(charging). When the current is negative, the battery is supplying voltage to the vehicle and therefore discharging.
This is a great idea to check what is happening with the alternator of your vehicle.
Battery Charge Level
|State of Charge
||Sealed or Flooded Lead Acid battery voltage
||AGM battery voltage