See also:

Changing the battery
You require a CR 2025 3 V cell battery. Take the mechanical key out of the SmartKey. Press mechanical key 2 into the opening in the SmartKey in the direction of the arrow until battery tra ...

Removing the mechanical key
•► Push release catch 1 in the direction of the arrow and at the same time, remove mechanical key 2 from the SmartKey. ...

DEF refill bottle
DEF refill bottles can be obtained at many gas stations or at an authorized Mercedes-Benz Center. Refill bottles without a threaded cap do not provide overfill protection. DEF may leak if over ...