Mercedes-Benz C-Class Saloon 2020, Owner'S Manual

Page: 79 / 557

#
Insert the new battery into battery compart‐
ment 3 . Observe the positive pole marking
in the battery compartment and on the bat‐
tery when doing this.
#
Push in battery compartment 3 .
#
Re-attach cover 1 and push it until it
engages.
Problems with the key, troubleshooting
You can no longer lock or unlock the vehicle
Possible causes:
R
The key battery is weak or discharged.
R
The key is faulty.
#
Check the battery using the indicator lamp
(
/
page 73).
#
Replace the key battery, if necessary
(
/
page 75).
#
Use the emergency key to lock or unlock
(
/
page 79).
#
Have the key checked at a qualified specialist
workshop.
There is interference from a powerful radio
signal source
The key function is impaired by, for example:
R
high voltage power lines
R
mobile phones
R
electronic devices (notebooks, tablets)
R
shielding due to metal objects or induction
loops for electrical gate systems or auto‐
matic barriers
#
Make sure that there is sufficient distance
between the key and the potential source of
interference.
You have lost a key
#
Have the key deactivated at a qualified spe‐
cialist workshop.
#
If necessary, have the mechanical lock
replaced as well.
Doors
Notes on the additional door lock
The additional door lock is only available for
vehicles for the United Kingdom.
& WARNING Risk of injury to persons
inside the vehicle when the additional
door lock is activated
If the additional door lock is activated, the
doors can no longer be opened from the
inside.
#
Never leave persons, in particular chil‐
dren, unattended in the vehicle.
#
If there are persons in the vehicle, do
not activate the additional door lock.
The additional door lock is automatically activa‐
ted in the following situations:
R
The vehicle is locked using the key.
R
The vehicle is locked using KEYLESS-GO.
76 Opening and closing
Internal use only