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669619 Removing and installing control unit for trailer hitch


WM 669619 Removing and installing control unit for trailer hitch

Preliminary work

Remove side trim panel on the right for rear luggage compartment. -> 700319 Removing and installing side trim panel for rear luggage compartment - "Removing" section 700319 Removing and installing rear luggage compartment side-trim panel.

Removing control unit for the trailer hitch

WARNING

Risk of destruction of electrical and electronic components.

-> Before removing the control unit for the towbar, switch off the ignition and remove the ignition key.





Overview of control unit for trailer hitch

1. Release both electrical connectors -arrows A- and pull them off -arrows B-.





Pulling off connectors and removing control unit

2. Unscrew the fastening screw -arrow 1- and lift the control unit up and out -arrow C-.





Pulling off connectors and removing control unit

Installing control unit for the trailer hitch

1. Insert control unit into the holder -arrow A- and screw in the fastening screw -arrow 1-.





Tighten control unit and connect plug

2. Position and push on both plugs -arrows B- until the locking tabs -arrows C- are felt to engage.





Tighten control unit and connect plug

Coding the control unit for the trailer hitch

Extracting and changing coding

Information

- After the trailer coupling control unit has been replaced, the coding must be customised to the vehicle equipment so that the control unit knows which trailer coupling is installed and which functions are desired or necessary.

- Automated folding/pivoting is synonymous with comfort closing in power windows. Touching the button is sufficient to fold/pivot the trailer hitch. -> 669619 Removing and installing control unit for trailer hitch - "Information" section.

- The No automatic folding/pivoting option can be coded if there are doubts about safety. The button then must be kept pressed until the trailer hitch is completely retracted or extended. -> 669619 Removing and installing control unit for trailer hitch - "Information" section.

- With or without operating button; the operating button must be activated for the pivoting trailer hitch. This is of course not necessary for the detachable towbar.

Versions or equipment features can be read out and reactivated under the Coding menu item.

The following options are possible:

Operating pushbutton:
- With operating pushbutton
- Without operating pushbutton

Version:
- Trailer coupling with detachable ball hitch
- Trailer coupling with automatic folding out/swivelling of the ball hitch "Comfort folding"

Country:
- RoW
- USA (North America)

By actuating the F8 button the code is memorised. Where necessary erase fault memory.

Information

- If the coding does not match the vehicle equipment, faults may be displayed that are not really present.

- The control unit does not function without a valid coding entry.

Permissible combinations

Information

- Ensure that only permitted combinations and existing versions are coded.






Subsequent work

Install the side trim panel at rear right. -> 700319 Removing and installing side trim panel for rear luggage compartment - "Installing" section 700319 Removing and installing rear luggage compartment side-trim panel.