Mercedes-Benz S-Class 2020 Operator's Manual page 557

Warning/indicator lamp Possible causes/consequences and
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The driving characteristics, as well as steering and braking, may be greatly impaired.
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You could then lose control of the vehicle.
Observe the recommended tire pressure.
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Adjust the tire pressure if necessary.
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Stop the vehicle, paying attention to road and traffic conditions.
Check the tire pressure and the tires.
Display messages and warning/indicator lamps 555
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