Mercedes-Benz S-Class Operator's Manual page 296

Display messages
294
Display messages
Cruise Control Cruise Control
Inoperative Inoperative
Cruise Control Cruise Control
- - - mph - - - mph
Possible causes/consequences and M M Solutions
Cruise control is defective.
A warning tone also sounds.
Visit a qualified specialist workshop.
X
A condition for activating cruise control has not been fulfilled.
You have tried to store a speed below 20 mph (30 km/h), for
example.
If conditions permit, drive faster than 20 mph (30 km/h) and
X
store the speed.
Check the activation conditions for cruise control
X
( page 199).
Y