Mercedes-Benz 2009 GL320 BlueTEC Operator's Manual page 182

Controls in detail
Driving systems
In such a case, Distronic will switch off, and
the message DISTRONIC Currently
Unavailable – See Operator's Manual
appears in the multifunction display.
For cleaning and care of the Distronic system
sensor cover, see ( Y page 321).
If the message DISTRONIC Available
i
Again appears during driving, the dirt (e.g.
slush) has dissolved; Distronic works again,
if you reactivate it ( Y page 176).
Turns and bends
In turns or bends, Distronic may not detect a
moving vehicle in front, or it may detect one
too soon. This may cause your vehicle to
brake late or unexpectedly.
180
Offset driving
A vehicle traveling in your lane but offset from
your direct line of travel may not be detected
by Distronic. There will be insufficient
distance to the preceding vehicle.
Lane changing
Distronic has not yet detected the vehicle
changing lanes. There will be insufficient
distance to the lane-changing vehicle.
Narrow vehicles
Because of their narrow profile, the vehicles
traveling near the outer edges of the lane
have not yet been detected by Distronic.
There will be insufficient distance to the
preceding vehicles.