Tyre Defect Indicator

The Tyre Defect Indicator (TDI) monitors the air pressure in the tyres at all road speeds. This system is therefore able to detect a possible loss of air by checking the wheels' speed of rotation.

Since the roll radius of the tyres alters as pressure decreases, the wheel rotation speed changes accordingly and is measured precisely by the Anti-Lock Braking System (ABS) sensors on the wheels. A warning light in the instrument panel and a warning signal alert the driver in the event of a loss of pressure.