Sound System: Intermittent Loss Of Sound After Engine Start (LI82.62-P-058583)

Publication date: 2014-07-15
Reference number: LI82.62-P-058583

SOUND SYSTEM: INTERMITTENT LOSS OF SOUND AFTER ENGINE START

TECHNICAL SERVICE BULLETIN

Reference Number(s): LI82.62-P-058583 Version 3, Date of Issue: July 15, 2014

MERCEDES-BENZ:	Model 166, 231 with code 810 (Harman Kardon Logic 7 surround sound system)
DESIGN GROUP:	82.62 Loudspeakers, amplifiers, antennas
REASON FOR CHANGE:	Cause adjusted, Remedy adapted

COMPLAINT

Intermittently no audio output, regardless of the selected audio source (radio, CD, USB) immediately after engine start.

When the complaint is active, the COMAND Online control unit (A40/3) or Audio20 control unit (A2) can still be operated. However, when the MOST ring subscribers are selected (Media Interface, SDAR), the fault message "Media Interface unavailable" or "Device unavailable" appears in the Audio/COMAND display (A40/8).

In the quick test, the fault codes "A27B: The specified and actual configurations of the MOST components are different" and/or "A22D: The automatic addressing or the programming is faulty" may be stored in the COMAND Online control unit (A40/3)/Audio20 control unit (A2).

NOTE: The complaint usually occurs in cold outside temperatures.

After bus idle (lock vehicle for approx. 5 minutes), the problem is usually rectified temporarily.

CAUSE

Software release of control units of sound system (N40/3) or SDARS (N87/5).

REMEDY

Perform software update of sound system control unit (N40/3) to software release 14/03.01 or higher.

This software release is available as of Xentry version 03/2014 or later.

Also perform a software update of the following control units, if installed:

Perform software update of SDARS control unit (N87/5) to software release 14/23.00 or higher.

These software releases are expected to be available as of Xentry version 09/2014 or later.

CONTROL UNIT/FAULT CODE

Control unit	Fault code	Fault text
Audio - Audio or COMAND (A2 - A40/3) (HU45)	A27B	The specified and actual configurations of the MOST components are different.
Audio - Audio or COMAND (A2 - A40/3) (HU45)	A22D	The automatic address allocation or the programming is faulty.

WORK UNITS

Op. no.	Operation text	Time	Damage code	Note
54-0991	CONTROL UNIT: ..... INSTALL SOFTWARE (AFTER QUICK TEST)		82557 EP