Retrofit wiring harness of hands-free system - AZ82.70-P-0005-02F

Expose VDA connection for telephone handset (A34) and separation point for portable cellular telephone (X39/37) in radio shaft.

Fig 1: Identifying VDA Connection For Telephone Handset
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Connect antenna for telephone handset (A34).
Connect VDA connection lead (5) to interface (4) and separation point for portable cellular telephone (X39/37).

Fig 2: Connecting Antenna For Telephone Handset
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Expose hands-free microphone interface (B25) present behind overhead control panel control module and connect microphone (6).
Glue microphone (6) onto mirror base as shown in figure with double-sided adhesive tape (contained in parts kit).
Align microphone so that pickup opening points towards driver.
Connect all controls and battery for operational check.
Avoid error messages from unconnected control modules.

Fig 3: Identifying Glue Microphone Onto Mirror Base
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
Insert test telephone in portable cellular telephone holder and set microphone sensitivity with "Micro" adjustment screw (arrow) on interface box (4).
Adjust so that feedback and whistling are not audible and the volume is optimum for speaking and listening.
Disconnect battery again.
Fasten interface box (4) and connection leads at rear in radio shaft as shown in figure with double-sided adhesive tape.

Fig 4: Identifying Interface Box
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.