The activation of this (amber yellow) "warning" indicates that the engine coolant temperature is high.
It is activated when the temperature reaches 121C (250f).
Note
In this case, stop the vehicle and switch the engine off immediately; make sure that the fans are working.

Low hands free key (hf) battery level
Steering release error - steering still lockedMenu 2 on/off function
This function turns off and back on the menu 2.
If menu 2 is disabled, the functions for average fuel
consumption (cons.Avg), instantaneous fuel consumption
(cons.), Average speed (speed avg), trip time (trip time)
and air temperature (air) will no longer be displayed in the
"main screen ...
Dds diagnosis instrument
The main functions of the dds diagnosis instrument can be summarised as
follows:
Retrieval of errors (faults) of the ignition-injection system stored in
the engine control unit memory and their subsequent
deletion, if required.
Reading of engine parameters (rpm, coolant and air temperat ...
Refitting the air filters
Apply universal sealant in the air duct (2) and (6) groove (d).
Fit seal (7) in the groove (d) having care to place it correctly in the relevant
seat so as to avoid abnormal wrinkles.
Pull out the filter cartridge (1) from the seat in the airbox.
Position the rh air duct (2).
Start ...