See also:

Contacts
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Functional readiness of the airbag system
When the ignition is switch on, the warning lamp in the instrument cluster lights up briefly and thereby indicates the operational readiness of the entire airbag system and the belt tensione ...

Ignition on
Automatic transmission: press the Start/Stop button, and do not press on the brake pedal at the same time. Manual-shift transmission: press the Start/Stop button, and do not press on the clutch ...