Trailer coupling socket wiring harness, removal and installation

AR31.19-P-1400GQA

Trailer coupling socket wiring harness, removal and installation

22.11.2019

Model

166.0/8

as of model year 2016

with code 550 (Trailer coupling)

except code 460 (Canada version)

except code 494 (US version)

except code 496 (Mexico version)

1

Crossmember

20.3

Grommet

20.5

Grommet

20

Wiring harness for trailer coupling socket

20.4

Housing

20.6

Black 2-pin coupling

20.7

Black 5-pin connector

20

Wiring harness for trailer coupling socket

W7/9

Trailer hitch ground point

br1

Brown line

20

Wiring harness for trailer coupling socket

20.1

Black, 24-pin connector

N28/1

Trailer recognition control unit

 Danger

Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)

Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.

AS00.00-Z-0035-01A

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

Topical note

General information on handling vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system

AH00.00-Z-0300-01A

Topical note

Information on preventing damage to electronic components due to electrostatic discharge

AH54.00-P-0001-01A

 

Remove/install

1

Remove rear bumper

Model 166.0
as of model year 2016
with code 550 (Trailer coupling)
except code 460 (Canada version)
except code 494 (US version)
except code 496 (Mexico version)

AR88.20-P-2200GQ

Model 166.8
as of model year 2016
with code 550 (Trailer coupling)
except code 460 (Canada version)
except code 494 (US version)
except code 496 (Mexico version)

AR88.20-P-2200GQA

2

Disconnect battery ground line

AR54.10-P-0003GZ

3

Remove park pawl battery

Model 166.8
as of model year 2016
with code 4U7 (Start/stop voltage dip protector)
with code 550 (Trailer coupling)
except code 460 (Canada version)
except code 494 (US version)
except code 496 (Mexico version)

AR54.10-P-0121GQA

4

Unlock black 24-pin connector (20.1) and detach from trailer recognition control unit (N28/1)

5

Detach brown line (BN1) from trailer hitch ground point (W7/9)

 Trailer hitch ground point

*BA00.19-P-1007-01G

6

Remove trailer hitch socket housing

AR31.19-P-1350GQA

7

Detach trailer hitch socket wiring harness (20) from cross member (1)

8

Detach grommet (20.3) from rear center section

9

Guide trailer hitch socket wiring harness (20) and grommet (20.3) through opening in rear center section to outside

10

Twist housing (20.4) in direction of arrow

 The housing (20.4) is locked by means of a quick-release coupling (arrow).

11

Detach grommet (20.5) from housing (20.4)

12

Push housing (20.4) toward trailer hitch socket wiring harness (20)

13

Unlock black 2-pin connector (20.6) and detach

14

Unlock black 5-pin connector (20.7) and remove

15

Remove trailer hitch socket wiring harness (20)

16

Install in the reverse order



Check

17

Perform function check of light signals at trailer socket



AN31.19-P-8100-06GQY

18

Perform function check of fully-electric tilt-down trailer hitch

 See Owner's Manual.

 Ground points

Number

Designation

Model 166

BA00.19-P-1007-01G

Trailer hitch ground point

W7/9

Nm

10