Mercedes-Benz 190 E 2.6 1989 Owner's Manual page 27

Examples of Air Flow Adjustments
g | Press to defrost or quickly defog windows.
Maximum heated air is'directed to the windshield and side
windows, independent of the temperature setting (1),
mode control (3) and fan speed control lever (4) position.
The air volume through outlets (7) may be adjusted with
levers (8) as desired.
| Press to defog the windshield from inside.
Air is directed to the windshield in the heating or cooling
mode. Press button H of mode control (3) and increase
fan speed for a short period with lever (4). Adjust levers (8)
for the desired air flow through outlets (7).
It is possible for condensation to form on the outside of
the windshield in humid weather in this mode. If this hap­
pens, change the air flow or decrease the fan speed.