Installation instructions:
Electrical system for towing hitch
Connecting the trailer control module
14. Plug the 12-pin and the 18-pin plugs into the trailer control module (Fig. 1/5).
15. Secure the trailer control module in the left-hand area of vehicle's rear using some velcro
tape.
16. Insert the supplied miniature relay (Fig. 1/2) into the relay socket. Secure the relay socket on
the cable harness using cable ties.
17. Let the quick-connect receptacles of the red and red/black cables (Fig. 2/4+5) of the cable
harness lock into place in one of the fuse holders each (Fig. 2/3).
18. Install the yellow clip (Fig. 2/6).
19. Insert the fuse (Fig. 2/2) and fit the cover (Fig. 2/1).
Note
Ensure sufficient strain relief and correct installation of the fuse holder.
20. Connect the 2-pin plug to the matching counterpart on the vehicle's cable harness in the
luggage trunk rear left area (Fig. 1/3).
21. Only for 13-pin trailer socket:
Using the 3-pin connector for the constant plus extension kit (Fig. 1/3), the functions "constant
plus", "charging lead" and "ground for charging lead" can be retrofitted.
The constant plus extension kit is available from specialist shops under the Westfalia part no.
300 025 300 113.
Checking correct operation
22. Reconnect the ground of the vehicle's battery.
23. Check the trailer function with the help of a suitable test instrument (with load resistors) or
with the help of a trailer.
24. Secure all cables using cable ties.
25. Refit any parts removed for installation.
Fiat Idea / Lancia Musa
306 240 391 101 - 002 - 48/04
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