AN31.19-P-8100-05EC Retrofitting Trailer Hitch Wiring Harness

AN31.19-P-8100-05EC Retrofitting Trailer Hitch Wiring Harness

Special Tools:

Component Identification:

Ensure that the wiring harnesses are not damaged by chafing, pinching or crushing as otherwise the respective wiring harness must be replaced.

1. Route black 6-pin coupling of the wiring harness of the trailer hitch (20) along existing lines to the installation place of the lock of the trailer hitch and fasten with cable ties.

2. Guide control unit wiring harness (22) along existing lines from trailer recognition control unit (N28/1) to rear SAM control unit with fuse and relay module (N10/2) and fix in place.
3. Check fuse assignment of blue fuse carrier (28).

Fuse assignment:
Slot 1 30 amp(s)
Slot 2 20 amp(s)
Slot 3 15 amp(s)
Slot 4 Not used
Slot 5 15 amp(s)
Slot 6 15 amp(s)
Slot 7 Not used

4. Plug the blue fuse carrier (28) into the slot with blue markings of the rear SAM control unit with fuse and relay module (N10/2).

5. Check fuse assignment of violet fuse carrier (27).

Fuse assignment:
Slot 1 30 amp(s)

6. Plug the violet fuse carrier (27) into the slot with violet markings of the rear SAM control unit with fuse and relay module (N10/2).

7. Connect brown lines from trailer hitch wiring harness (20) and from control unit wiring harness (22) to the right taillamp trunk ground point (W7/1).

8. Connect interior/trailer hitch electrical connection (X58/33).
For this purpose, connect white 2-pin connector of the control unit wiring harness (22) to the white 2-pin coupling of the trailer hitch wiring harness (20).

9. Strap down any excess length of control unit wiring harness (22) and trailer hitch wiring harness (20) behind the rear SAM control unit with fuse and relay module (N10/2).

10. Expose twisted brown line (br) and brown/red line (br/rt) of the Controller Area Network (data bus/CAN Bus) (CAN) wiring harness on the 52-pin yellow coupling of the rear SAM control unit with fuse and relay module (N10/2) as shown.
11. Route brown (br) CAN line and brown/red (br/rt) CAN line from control unit wiring harness to the 52-pin yellow coupling and cut off any unneeded excess as well as the 2-pin black coupling.
12. Connect brown (br) CAN line and brown/red (br/rt) CAN line from control unit wiring harness with the identical colored brown line (br) and brown/red line (br/rt) of the CAN wiring harness using potential distributors (23).
The voltage distributors (23) should be removed from the wiring harness repair kit.

13. Fit couplings (29) on the trailer recognition control unit (N28/1).
The couplings (29) are coded and cannot be mismatched.