Recommended Wiring Procedure For Brake Controller (31.19/03)

Publication date: 1999-08-01
Reference number: 31.19/03

RECOMMENDED WIRING PROCEDURE FOR BRAKE CONTROLLER

TECHNICAL SERVICE BULLETIN

Reference Number(s): 31.19/03, Date of Issue: August 1999

MODEL 163 - RECOMMENDED WIRING PROCEDURE DURING BRAKE CONTROLLER INSTALLATION

Model(s): 1998-on Mercedes-Benz ML 320: 1999-on Mercedes-Benz ML 430

Group: 31 - Chassis, Trailer Hitch

Bulletin No.: T-SI-MBUSA-31.19/03

Date: August 1999

SERVICE INFORMATION

NOTE: This document is only to be used as a guide for locating the recommended point at which to connect an electric brake controller to an M-Class vehicle's brake lamp circuit and trailer socket. There are various makes and models of brake controllers on the market and none have been tested or approved for use by Mercedes-Benz. Further, all work of this type must be performed in strict accordance to the Installation Instructions and set up procedures as supplied by the brake controller manufacturer.

PROCEDURE

Locate the 3-wire to 2-wire converter (N28, Fig. Fig 1 ) that is built into the wiring harness supplied with the trailer hitch kit (part no. Q6 31 0002).
Cut the orange circuit #1660 wire (A) at a point after N28, but before the point the harness exits the vehicle through the grommet.
The end of the orange wire # 1660 that comes from N28 should be connected to a new wire (B) and run to the brake controller. This wire supplies the brake light signal to the controller and only needs to be of wire size 1mm² or equivalent.
A second wire (C) should be run from the brake controller output to the end of the orange wire # 1660 that runs to the trailer socket (X58). This is the designated electric brake terminal. Refer to the brake controller installation instructions for proper wire size.
Follow the brake controller installation instructions for connecting power and ground circuits. Most recommend using a circuit breaker and connecting the power and ground circuits directly at the battery (G1).
Carefully read and follow the brake controller installation instructions for all mounting, testing, and adjustment procedures.

NOTE: Controller must be mounted within reach of driver.

NOTE: Follow the brake controller's instructions for Installing overcurrent protection and for all wire routing and size requirements!

NOTE: Brake controller must be set up, adjusted, and tested according to the instructions supplied with the controller.

Fig 1: Brake Controller Installation Wiring Diagram