Fitting the removable ball coupling

Fig. 91 Overview: removable ball coupling

First read and observe the introductory information and safety warnings

The removable ball coupling is located under the luggage compartment floor with the vehicle toolkit.

Key for :

1. 1
   Cap
2. 2
   Ball coupling
3. 3
   Retaining balls
4. 4
   Catch for locking mechanism
5. 5
   Shank
6. 6
   Centring device
7. 7
   Handwheel
8. 8
   Keys
9. 9
   Cover
10. 10
    Gap (pre-tensioned ball coupling)
11. 11
    Green marking on the ball coupling
12. 12
    Green marking on handwheel
13. 13
    Red marking on handwheel

Step 1: Preparations

• Before using the ball coupling for the first time, make a note of the number stamped on the key. This can be used if you need to acquire a replacement key.

• Remove the cover underneath the rear bumper. To do this, reach into the recess and pull the cover down and off. Stow the cover in the vehicle.

• Remove the sealing plug from the ball coupling mounting.

• Move the trailer socket down from the right-hand side and then as far up as possible to the left. This gives you access to the ball coupling mounting.

• Check to ensure that the mounting, handwheel , shank ⑤ and retaining balls ③ of the ball coupling are all clean and not damaged . Clean as necessary.

Step 2: Setting the ball coupling to the "ready" position

The ball coupling cannot be fitted properly unless the spring mechanism inside the ball joint is in the ready position.

• Take the ball coupling in your left hand.

• Remove the cover from the lock and insert the key ⑧ into the lock.

• Turn the key clockwise.

• Use your right hand to pull out the handwheel ⑦ in the direction of arrow 1 and keep it in this position .

• Turn the handwheel ⑦ in the direction of arrow 2 until it engages. The ball coupling is now in the ready position. The red marking ⑬ on the handwheel must point towards the green marking ⑪ on the ball coupling. The handwheel is clearly visible in front of the ball coupling. The distance between the two is approximately 4 mm ⑩.

• Check to see whether all retaining balls ③ can be pressed fully into the ball coupling mount ⑤.

Step 3: Attaching the pre-tensioned ball coupling to the vehicle

Do not touch the handwheel once the ball coupling has been pre-tensioned. When engaged, the handwheel will spring back to its original position and could cause injury .

• Guide the pre-tensioned ball coupling into the mounting pipe from below.

• Push the ball coupling firmly upwards until it engages. Both of the centring devices must engage in the insertion point on the vehicle.

• The handwheel has now returned to its original position. There is no longer a gap between the handwheel and the ball coupling.

• Turn the key ⑧ anticlockwise in the handwheel and remove it.

• If the setting is correct, you will not be able to turn the handwheel or pull it out.

• Put the cover ⑨ over the lock and place the key in the vehicle toolkit.

Step 4: Safety check

Check to see whether the ball coupling is attached properly:

• The green marking on the handwheel must point towards the green marking ⑪ on the ball coupling.

• The handwheel must rest on the ball coupling and there may be no gap between them.

• Shake the ball coupling or pull it down with some force. It must sit firmly in the mounting .

• The lock must be locked and the key removed. The cover must be fitted over the lock in the handwheel.

Improper fitting of the ball coupling can cause injuries and accidents.

• Only use the ball coupling when it is fitted properly.

• If the smallest diameter on the ball coupling is smaller than 49 mm, do not use the towing bracket.

• The ball coupling is heavy. When checking whether it is secure, the ball coupling could fall off and cause injuries.

• Do not touch the handwheel once the ball coupling has been pre-tensioned. When the ball coupling is pressed into the mounting, the handwheel will spring back to its original position.

• If the ball coupling will not fit properly, the towing bracket should be checked by a qualified workshop.

• Do not use the towing bracket if the ball coupling does not engage properly or if you are unable to set it to the "ready" position.

• Do not use the towing bracket if you are unable to remove the key from the handwheel once the ball coupling has been mounted. This means that ball coupling is not locked properly.

• Always fasten the ball coupling securely in the luggage compartment once it has been removed.

NOTICE

• The mounting on the vehicle, handwheel, shank and ball coupling retaining balls must all be clean and undamaged. Otherwise you may not be able to lock the ball coupling securely.

• Do not aim a high-pressure hose or steam cleaner directly at the ball coupling mounting. This could wash the grease required for lubrication out of the mounting.