Audi A3  Setting off  Towing a trailer  Removable towing bracket
Applies to vehicles: with removable towing bracket
The spring mechanism inside the ball joint must be in the "ready" position.
Check that the red marking -2- Fig. 1 on the knob is inside the green zone on the ball joint.
Check that the locking ball -1- is inside the hole in the shaft section of the ball joint.
Check that the knob protrudes visibly from the ball joint, so that there is a clear gap -3- between the knob and the ball joint.
The ball joint can only be installed if the internal spring mechanism is in the ready position.
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