Using seat belts :

Check the condition of all seat belts regularly.

Keep the seat belts clean.

Avoid allowing any foreign bodies or fluids to get on to the seat belt or latch plate or into the slot for the seat belt buckle.

Do not trap or damage the seat belt and latch plate, for example when closing the door.

Never remove, modify or repair the seat belt or any part of the belt fixture system.

Always fasten the seat belt correctly before every journey and keep it fastened while the vehicle is in motion.
Twisted seat belt
If it is difficult to remove the seat belt from the belt guide, the seat belt may have become twisted if it was returned too quickly into the side trim:
Fasten the seat belt even if you are unable to undo the twist. However, the twist should not be in part of the seat belt that comes into direct contact with the body. The twist should be corrected immediately by a qualified workshop.

WARNING
Using seat belts
Fastening and unfastening seat belts4-Pin Heated Oxygen Sensor (HO2S), Removing and Installing
Note
Do not repair the heated oxygen sensor wires. Repairing may
result in malfunctions.
Use the faulty sensor as a guide for installing all of the
accompanying attachments, cable ties or marking bands.
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Two-Part HS Premium Filler
Definition:
Two-Part HS Premium Filler -LVM 013 171 A4-, dark gray
Two-Part HS Premium Filler -LGF 013 007 A4-, light gray
Two-Part HS Premium Filler -LGF 013 100 A4-, white
...
Vehicle identification data
Fig. 15 A: Vehicle data sticker: example
shows a vehicle with engine code CCZB ③. B: Type plate
Fig. 16 Vehicle identification number
First read and observe the introductory information
and safety warnings
Vehicle identification number (FIN)
The vehicle identification number can be read ...