Automatic Belt Retractor (Locking Function), Checking

The automatic belt retractor has two locking functions.

• The first locking function is initiated by the belt being jerked out of the automatic belt retractor (belt extraction acceleration).

Test 1

-- Pull the seat belt webbing out of the automatic belt retractor with a firm jerk.

• No locking effect - replace the entire seat belt with seat belt latch.
• If difficulties are experienced when pulling out or retracting belt, first check whether position of the belt retractor has been altered.
• The second locking function is initiated by change in vehicle velocity (vehicle-dependent locking function).

Test 2

• For safety reasons, road test should be carried out on traffic-free stretch to ensure that other drivers/pedestrians etc. are not endangered.

-- Fasten the seat belt.

-- Accelerate the vehicle to 20 km/h and then perform a hard braking maneuver with the foot brake.

• Replace the entire seat belt with the seat belt latch if the seat belt is not locked by locking mechanism during the braking procedure.