Seat 2017 IBIZA SC Owner's Manual page 19

Seat belts 17
1)
The warning lamp  in the instrument panel lights up
if the driver or
1)
passenger seat belt is not fastened when the ignition is switched on. More-
1)
over, an audible warning is heard on exceeding 25 km/h. This signal will
stop after 90 seconds or when the seat belt is fastened.

The warning lamp* is switched off if the driver seat belt is fastened while
the ignition is switched on.
1)
Depending on the model version
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