Mercedes-Benz C-Class 2015 Owner's Manual page 88

Problems with the key
Problem
You can no longer lock or
unlock the vehicle using
the key.
You can no longer lock or
unlock the vehicle using
KEYLESS-GO.
Possible causes/consequences and M M Solutions
The key battery is discharged or nearly discharged.
Check the key battery (
X
( page 83).
Y
If this does not work:
Unlock ( page 88) or lock (
X
Y
emergency key element.
There is interference from a powerful source of radio waves.
Unlock ( page 88) or lock (
X
Y
emergency key element.
The key is faulty.
Unlock ( page 88) or lock (
X
Y
emergency key element.
Have the key checked at a qualified specialist workshop.
X
KEYLESS-GO was deactivated.
Reactivate KEYLESS-GO (
X
The key battery is discharged or nearly discharged.
Check the key battery (
X
( page 83).
Y
If this does not work:
Unlock ( page 88) or lock (
X
Y
emergency key element.
There is interference from a powerful source of radio waves.
Unlock ( page 88) or lock (
X
Y
emergency key element.
There is a fault with KEYLESS-GO.
Lock/unlock the vehicle using the remote control function of the
X
key.
Have the vehicle and key checked at a qualified specialist work-
X
shop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function:
Unlock ( page 88) or lock (
X
Y
emergency key element.
Have the vehicle and key checked at a qualified specialist work-
X
shop.
page 83) and replace if necessary
Y
page 88) the vehicle using the
Y
page 88) the vehicle using the
Y
page 88) the vehicle using the
Y
page 81).
Y
page 83) and replace if necessary
Y
page 88) the vehicle using the
Y
page 88) the vehicle using the
Y
page 88) the vehicle using the
Y
Key
85
Z