Mercedes-Benz 500 SEC Operator's Manual page 86

Snow chain switch
Driving with Snow Chains
When driving with snow chains, press
the symbol side of the snow chain
switch, located on the instrument panel
(the indicator lamp in the switch comes
on) to obtain maximum possible
traction.
This mode is effective at speeds up to
25 mph (40 km/h). It remains stored in
memory up to 37 mph (60 km/h) and
automatically engages again when the
vehicle speed drops below 25 mph (40
km/h).
The mode is canceled in memory
above 37 mph (60 km/h) and the
indicator lamp in the switch goes out.
To switch off: press lower half of
switch (the indicator lamp in the
switch goes out).
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