"DDS" is a function in ABS MK60 ESP which identifies the pressure loss in the tire mathematically with the wheel speed sensors for ABS. The wheel speed is continuously monitored while driving, on each wheel. Loss of pressure in a tire, reduces its diameter and thus the wheel speed. If the system identifies such a speed difference, the warning light(red) is illuminated. "DDS" is a system that measures indirectly, as it only warns at air loss, but do not specify the tire position. The warning light illuminates at a pressure deviation of about 30 % compared with the other tires. At a disturbance in the system, the warning light (yellow) illuminates.