Mercedes-Benz M-Class Operator's Manual page 351

Using the 115 V power socket
To switch on: switch the ignition on.
X
Open flap =.
X
Insert the plug of the electronic device into
X
115 V power socket :.
Indicator lamp ; lights up.
To turn off: disconnect the plug from
X
115 V power socket :.
Ensure that you do not pull on the cord.
Features
349
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