Exactly what Ray said above.
Just reset the data and you'll get the range of the GOM to a "rated" standard at 3 miles per kWh consumption. The battery needs to be near room temperature.
Mercedes B-Class ED battery
36.0kWh total – 100% SOC (never used)
31.5kWh usable- 90.0% SOC (3 miles per kWh * 31.5 = 94 miles)
28.0kWh usable- 80.0% SOC (3 miles per kWh * 28.0 = 84 miles)
1.0 kWh unusable- 2.7% SOC
*** Mercedes consumption meter is calibrated so that 3.6 miles per kWh will show as 3.0 on the dash, as will 3.0 miles per kWh show as 2.5 on the dash. The correction factor is 83.333%, or 1.2
As the battery degrades over time, those mileage figures will drop. Also, know that if your car's battery is at room temperture, you can reset the GOM and know that whatever miles are shown with a "full charge" (either normal 80% or extended charge at 90%), if you divide by 3, that is the usable kWh.
Then , you can calculate the degradation over time. At 87 miles shown with a extended charge, 87 / 94 = 92.5% of new capacity.
