Mercedes-Benz CL-Class 2006 Owner's Manual page 251

Controls
Key positions
Removing the KEYLESS GO button
You can pull the KEYLESS GO button out of
the ignition lock and start the vehicle using
a key in the conventional way.
P15.10-2192-31
1 KEYLESS GO button
2 Ignition lock
i
When you change back from using the key
to using the KEYLESS GO function, the system
requires 2 seconds recognition time before you
will be able to use the KEYLESS GO button as
normal.
i
It is not necessary to remove the KEYLESS
GO button from the ignition lock when you leave
the vehicle.
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