Mercedes-Benz M-Class Owner's Manual page 79

Key
76
Problems with the key
Problem
You cannot lock or
unlock the vehicle
using the key.
You can no longer lock
or unlock the vehicle
using KEYLESS-GO.
You have lost a key.
You have lost the emer-
gency key element.
Possible causes/consequences and M Solutions
The key battery is discharged or nearly discharged.
Try again to lock/unlock the vehicle using the remote control
X
function of the key. Point the tip of the key at the driver's door
handle from close range and press the % / & button.
If this does not work:
Check the key battery (
X
( page 75).
Y
Lock ( page 79) or unlock (
X
Y
the emergency key element.
The key is faulty.
Lock ( page 79) or unlock (
X
Y
the emergency key element.
Have the key checked at a qualified specialist workshop.
X
There is interference from a powerful source of radio waves.
Lock/unlock the vehicle using the remote control function of
X
the key. Point the tip of the key at the driver's door handle from
close range and press the % / & button.
There is a fault with KEYLESS-GO.
Lock/unlock the vehicle using the remote control function of
X
the key. Point the tip of the key at the driver's door handle from
close range and press the % / & button.
Have KEYLESS-GO checked at a qualified specialist workshop.
X
If this does not work:
Check the key battery (
X
( page 75).
Y
Lock ( page 79) or unlock (
X
Y
the emergency key element.
Have the key deactivated at a qualified specialist workshop.
X
Report the loss immediately to the vehicle insurers.
X
If necessary, have the locks changed as well.
X
Report the loss immediately to the vehicle insurers.
X
If necessary, have the locks changed as well.
X
page 74) and replace it if necessary
Y
page 79) the vehicle using
Y
page 79) the vehicle using
Y
page 74) and replace it if necessary
Y
page 79) the vehicle using
Y