Cell Phone - Bluetooth(R) Choppy, Echo/Distortion

Mercedes Benz C 250 (204.052) (CANADA) V6-2.5L (272.921) Technical Service Bulletin # LI82-70_P-042940 Date: 120409

Cell Phone - Bluetooth(R) Choppy, Echo/Distortion

Blue Tooth Hands-free Telephone Conversation Choppy, Echo/Distortion Detected Especially By The Land-line Caller

Topic number LI82.70-P-042940

Version 1

Design group 82.70 Cellular telephone, voice control system (VCS)

Date 04-09-2012

Validity Model 204 up to chassis A182847 or F171433 with COMAND APS including DVD changer, code 512, or COMAND APS (with navigation), code 527

Reason for change

Complaint:

If you receive customer reports in the above model vehicles of the Blue Tooth Telephone hands-free conversation Audio quality being choppy,

produces echo on both sides but especially detected by the landline.

Cause:

Maybe due to a Software error in the COMAND Head Unit.

Remedy:

To remedy, please update the COMAND Head Unit software using DAS 02/08 (or later) and SD Telematics Disc PN A204 827 42 59 by following

the procedure below.

Update Procedure:

1. Turn Engine and Electrical Consumers OFF

2. Connect a Battery Charger & Start DAS

3. Proceed to menu: Control units --> Information and communication --> Audio, video navigation and Telematics --> COMAND APS --> ...-->

Control unit adaptations --> control unit programming.

Page 30

4. Follow the DAS prompts ... insert the SD Telematics CD into the Head Unit slot 1 of the changer and wait until the CD is recognized the

update process will start automatically Do NOT Turn Head Unit OFF during the update process (See figure 1 showing what the COMAND

screen looks like during the normal update process)

5. When process is complete, restart the Optical Ring and go back to: control unit adaptations --> Variant coding --> SCN Coding. Perform a

COMAND SCN Coding

NOTE:

You must perform SCN coding after the update even though the Head Unit is fully operational, otherwise, the update is not complete