NHTSA ID Number: 11007966
Manufacturer Communication Number: LI82.90-P-078381
TSB/Document Date: 2024-09-24
Summary
Complaint Display dark (total or partial) of one or more ASCM (AMG
) steering wheel button displays - see attachment. Note: There is no loss of vehicle functionality due to this complaint. Cause Software can cause a partial display on the ASCM. Remedy Please perform the following steps in the event of a total or partial display of the ASCM displays: 1. Perform a hard reset (disconnect power supply) of control unit A74/2 (ASCM) for 2 minutes. 2. Perform a software update of the A74/2 (ASCM), N145 (DRVU) and A26/17 (HU). 3. Reset the user profile via the head unit settings menu. (Full factory reset)
Display dark on ASCM AMG steering wheel buttons, code U88 (A74/2)
Topic number
LI82.90-P-078381
Version
1
Function group
82.90 - On-board communications system, multifunction steering wheel, central control functions
Date
9/17/24
Validity
Model series 206, model series 214, model series 223, model
series 236, model series 297, model series 295, model series
294, model series 232, 192, model series 254 with code U88.
Reason for change
Complaint
Display dark (total or partial) of one or more ASCM (AMG) steering wheel button displays - see attachment.
Note: There is no loss of vehicle functionality due to this complaint.
Attachments
File
Description
Darstellungsfehler_ASCM223.jpg
Example of partial display on ASCM
Cause
Software can cause a partial display on the ASCM.
Remedy
Please perform the following steps in the event of a total or partial display of the ASCM displays:
1.
2.
3.
Perform a hard reset (disconnect power supply) of control unit A74/2 (ASCM) for 2 minutes.
Perform a software update of the A74/2 (ASCM), N145 (DRVU) and A26/17 (HU).
Reset the user profile via the head unit settings menu. (Full factory reset)
23.09.2024 19:08
© Copyright Mercedes-Benz AG
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Page 1 / 2
4.
Perform initial start up of the N145DRVU and A26/17 HU.
If the symptom persists: create a TIPS case.
Disclaimer
NOTE: The information contained in this document is intended for use by trained, professional technicians with the knowledge
to properly and safely perform diagnosis and repairs on Mercedes-Benz vehicles, using Mercedes-Benz approved tools and equipment. It informs service technicians about conditions that could occur in certain vehicles and provides information that could assist in proper vehicle diagnosis, service, or repair. It does not indicate that a defect is present in any vehicle referenced in this document nor does it imply warranty coverage. DO NOT assume that a symptom or condition, or a described cause of a symptom or
condition, affects any particular vehicle or groups of vehicles, or that a described repair applies to any particular vehicle or groups
of vehicles. There can be multiple causes resulting in the same or similar symptoms or conditions described in this document, and
trained professional service technicians must use their diagnostic skills to make evaluations on a case-by-case basis. The information contained in this document does not guarantee warranty coverage nor does it extend the vehicle’s warranty in any way.
Symptoms
Chassis/suspension > Steering system > Multifunction steering wheel control buttons > Malfunction
Communication/information > Information display > Displays > Multifunction display > Function > Pixel errors/segments missing
Communication/information > Entertainment > Overall system/operation > Button nonfunctional
Control unit/fault code
Control unit
Fault text
N4 - On-Board Diagnostics (DRVU) (DRVU3)
-
A74/2 - Button group 'Lower multifunction steering wheel' (T- MFL-U) (ASCM223)
Operation numbers/damage codes
Op. no.
Operation text
23.09.2024 19:08
© Copyright Mercedes-Benz AG
Time
Damage
code
Note
4601C52
Left Display fault ASCM223
4601D52
Right Display fault ASCM223
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TSB/Document ID: LI82.90-P-078381
Replacement Service Bulletin Number:
MFR Communication Date: 2024-09-18
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: SUSPENSION
MFR Component System:
MFR Component Subsystem:
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