LI8270P0647261

Mobile phone in general: It is intermittently difficult for
the called party to understand the driver, background
noises are occasionally audible during a telephone call
Topic number
LI82.70-P-064726
Version
1
Design group
82.70 Cellular telephone, voice control system (VCS)
Date
08-22-2016
Validity
BR213
Reason for change
Reason for block
Complaint:
During a phone call, it is difficult for the called party to understand the driver, or interference/ background noises are
occasionally audible to the called party during a call.
Cause:
A) Possibble assembly of microphones (B25/20 or B25/21) in headliner
B) Wiring between microphone (B25/20 or B25/21) and head unit (A26/17).
-See PE82.85-P-2110-97DBA
Remedy:
A) Possible assembly of microphones (B25/20 or B25/21):
1. Remove reading lamp
2. Press finger on rear of microphone (on adhesive tape)
3. Remove microphone cap from the front
4. Push microphone from behind until it is firmly pressed into the headliner
5. Maintain pressure and press/clip cap into microphone from the front
B) Wiring between microphone (B25/20 or B25/21) and head unit (A26/17):
Check individual pins at connections X58/3 (microphone electrical connection) and at microphone (B25/20 or B25/21)
and at head unit (A26/17).
One of the fault codes (DTC) listed may be present.
Symptoms
Communication/information / Communication / Mobile phone / Telephone / Poor understanding
08-22-2016 2:21 PM
© Copyright Daimler AG
PRIESTM
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Communication/information / Communication / Mobile phone / Telephone / Driver cannot be heard
Communication/information / Communication / Mobile phone / Telephone / Driver can be poorly/hardly heard
Control unit/fault code
Control unit
Fault code
Fault text
A26/17 - Audio or COMAND
(Audio) (HU55)
B143A12
Microphone 1 has a malfunction. There is a short circuit to positive.
A26/17 - Audio or COMAND
(Audio) (HU55)
B143D11
Microphone 2 has a malfunction. There is a short circuit to
ground.
A26/17 - Audio or COMAND
(Audio) (HU55)
B143D13
Microphone 2 has a malfunction. There is an open circuit.
A26/17 - Audio or COMAND
(Audio) (HU55)
B143D12
Microphone 2 has a malfunction. There is a short circuit to positive.
A26/17 - Audio or COMAND
(Audio) (HU55)
B143A13
Microphone 1 has a malfunction. There is an open circuit.
A26/17 - Audio or COMAND
(Audio) (HU55)
B143A11
Microphone 1 has a malfunction. There is a short circuit to
ground.
Operation numbers/damage codes
Op. no.
Operation text
Time
Damage
code
Note
8210R EM Telephone function, poor communication quality/interference noise
WIS-References
Document number
Title
PE82.85-P-2110-97DBA
Wiring diagram for head unit
08-22-2016 2:21 PM
© Copyright Daimler AG
Note
PRIESTM
Allocation
Cause
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