NHTSA ID Number: 11020873
Manufacturer Communication Number: LI54.21-P-079510
TSB/Document Date: 2025-07-24
Summary
Complaint Diverse functional limitations in the vehicle in combination with various warning and fault messages in the instrument cluster display. Cause Communication timeouts mean that communication errors may occur in the on-board electrical system, which can result in various fault messages being displayed in the instrument cluster. This could be down to delayed feedback from the drivetrain control unit (N127) (CPC) to other control units networked to the CAN bus. Information: • It may not be possible to attribute any communication errors stored in the control units on the CAN bus to a specific cause. • In rare instances, there may be a brief activation of the yellow warning lamp for engine diagnosis or there may be a sporadic delay with the start enable. • There may not be any specific fault codes present that indicate a specific component. Remedy Do not replace any components!!! 1. Connect charger (see AR54.10-P-1127WT). Note: An adequate voltage from the on-board electrical system battery must be guaranteed for the entire duration of the work procedure. Otherwise the control units could be damaged if an undervoltage occurs. Information: Observe the operating instructions of the charger. Information: Use the charger to ensure an adequate voltage (at least 12.5 V) from the on-board electrical system battery. 2. Connect diagnostic system (see AD00.00-P-2000-06FR). Note: Always use the latest XENTRY Diagnostics software release. Information: Strict compliance with the operation steps in XENTRY Diagnostics is absolutely essential. 3. Select control unit N127 (CPC) via the direct link using XENTRY Diagnosis. Information: To do so, select the following menu items: Control units view → Drive systems → N127 - "Powertrain" control unit (CPC). 4. Update software for control unit N127 (CPC) (see AR54.21-P-0014-01Y). Info: To do so, select the following menu items: Adaptations → Control unit update → Update control unit software. Information: You are then automatically guided through the steps "Update of control unit software" and "SCN coding". Always observe the following operation steps at all times. 5. Disconnect diagnostic device from vehicle (see AD00.00-P-2000-06FR). 6. Disconnect charger from vehicle (see AR54.10-P-1127WT).
If the PDF is very large, it may not load in the preview below.
Some older TSBs had multiple PDFs — visit the NHTSA Website to view all PDFs.
If the TSB PDF does not show, download or view it on the NHTSA Website.
Click on the (+) Plus Sign
Then Click on Associated Document(s)
- Advanced VCI Box, Industry-leading J2534 Pass-Thru...
- High-Speed OEM-Level Diagnostics & Programming: Unlock true...
- Coverage for 17 Car Brands & Ultra Reliability: Works...
- User-Friendly RLink Platform & Expert Support: TOPDON’s...
- 6.6 ft USB-C Cable & Portable Storage Case: The RLink J...
This product presentation was made with AAWP plugin.
Search NHTSA Database for Recalls
Search NHTSA Database for Vehicle Investigations
View Latest Vehicle Investigations
Search NHTSA Database for Vehicle Complaints
View Latest Vehicle Complaints
TSB/Document ID: LI54.21-P-079510
Replacement Service Bulletin Number:
MFR Communication Date: 2025-07-17
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: ELECTRICAL SYSTEM
MFR Component System:
MFR Component Subsystem:
Previous TSB | Next TSB |
Diverse functional limitations in the vehicle in combination with various warning and fault messages in the instrument cluster display
Topic number
LI54.21-P-079510
Version
1
Function group
54.21 - Control units / basic modules
Date
7/16/25
Validity
Model series 206, 214, 223, 236, 254 (all vehicles
with powertrain control unit (N127) (CPC) of control unit
variant
"CPC3")
Reason for change
null
Complaint
Diverse functional limitations in the vehicle in combination with various warning and fault messages in the instrument
cluster display.
Cause
Communication timeouts mean that communication errors may occur in the on-board electrical system, which can result in various fault messages being displayed in the instrument cluster.
This could be down to delayed feedback from the drivetrain control unit (N127) (CPC) to other control units networked
to the CAN bus.
Information:
•
•
•
It may not be possible to attribute any communication errors stored in the control units on the CAN bus to a specific cause
In rare instances, there may be a brief activation of the yellow warning lamp for engine diagnosis or there may
be a sporadic delay with the start enable.
There may not be any specific fault codes present that indicate a specific component.
Example image: Fault messages in instrument cluster:
16.07.2025 20:15
© Copyright Mercedes-Benz
AG
CCUSHWA
Page 1 / 4
The reason for this could be down to delayed feedback from the control unit CPC3 to other control units networked on
the CAN bus.
Attachments
File
Description
1.jpg
Remedy
Do not replace any components!!!
*******************************************************************************************************
1.
Connect charger (see AR54.10-P-1127WT).
Note: An adequate voltage from the on-board electrical system battery must be guaranteed for the entire duration of the work procedure. Otherwise the control units could be damaged if an undervoltage occurs.
Information: Observe the operating instructions of the charger.
16.07.2025 20:15
© Copyright Mercedes-Benz AG
CCUSHWA
Page 2 / 4
Information: Use the charger to ensure an adequate voltage (at least 12.5 V) from the on-board electrical system
battery.
2.
-------------------------------------------------------------------------------------------------------------------------------Connect diagnostic system (see AD00.00-P-2000-06FR).
Note: Always use the latest XENTRY Diagnostics software release.
Information: Strict compliance with the operation steps in XENTRY Diagnostics is absolutely essential.
3.
-------------------------------------------------------------------------------------------------------------------------------Select control unit N127 (CPC) via the direct link using XENTRY Diagnosis.
Information: To do so, select the following menu items: Control units view → Drive systems → N127 - "Powertrain" control unit (CPC)
4.
-------------------------------------------------------------------------------------------------------------------------------Update software for control unit N127 (CPC) (see AR54.21-P-0014-01Y).
Info: To do so, select the following menu items: Adaptations → Control unit update → Update control unit software.
Information: You are then automatically guided through the steps "Update of control unit software" and "SCN coding". Always observe the following operation steps at all times
5.
-------------------------------------------------------------------------------------------------------------------------------Disconnect diagnostic device from vehicle (see AD00.00-P-2000-06FR).
6.
-------------------------------------------------------------------------------------------------------------------------------Disconnect charger from vehicle (see AR54.10-P-1127WT).
WIS-References
Document number
Title
Note
AR54.10-P-1127WT
Maintain on-board electrical system
Maintain on-board electrical system
voltage for testing and diagnosis work voltage for testing and diagnosis work
on the vehicle
on the vehicle
AD00.00-P-2000-06FR
Connect/disconnect diagnostic device
AR54.21-P-0014-01Y
Program control unit
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
16.07.2025 20:15
© Copyright Mercedes-Benz AG
CCUSHWA
Page 3 / 4
Overall vehicle > Power supply > Battery/On-board electrical system > Battery function > Damage
Communication/information > Assistance and warning systems > Parking assist > PARKTRONIC > Acoustic warning
malfunction > General
Overall vehicle > Safety and locking system > Drive authorization system DAS > Electronic ignition lock/steering lock
> Does not receive turn authorization
Overall vehicle > Safety and locking system > Drive authorization system DAS > Electronic ignition lock/steering lock
> Malfunction
Overall vehicle > Power supply > Battery/On-board electrical system > Battery/on-board electrical system indicator
lamp > Battery charge indicator/consumer shutoff > Illuminates white
Power generation > Engine management > Indicator lamp > Engine diagnosis > lit
Communication/information > Information display > Displays > Multifunction display > Function > Malfunction
Communication/information > Information display > Displays > Multifunction display > Multifunction display, error
messages > Implausible messages despite properly functioning message systems
Communication/information > Information display > Indicator lamp > Malfunction
Communication/information > Information display > Indicator lamp > lit
Overall vehicle > Networking > Diagnosis/software > Software update (add-on)
Overall vehicle > Networking > Diagnosis/software > Current problems
Overall vehicle > Power supply > Battery/On-board electrical system > Battery/on-board electrical system display
message > Battery/Alternator - Serviced Required
Overall vehicle > Networking > CAN/FlexRay communication > Malfunction
Overall vehicle > Networking > LIN communication > Malfunction
Overall vehicle > Networking > Gateway communication > Malfunction
Communication/information > Information display > Displays > Multifunction display > Multifunction display, error
messages > Drivetrain - Malfunction (white warning message)
Overall vehicle > Power supply > Fuel cell > Malfunction
Communication/information > Assistance and warning systems > Blind spot assist > Malfunction
Control unit/fault code
Control unit
Fault text
N127 - Control unit "Drivetrain" (PTCU) (CPC3AMG)
-
N127 - Control unit "Drivetrain" (PTCU) (CPC3)
-
Operation numbers/damage codes
Op. no.
Operation text
Time
Damage
code
541011
Perform quick test
H
5440Z
540991
Program and code CPC3 control unit
(after quick test)
H
5440Z
16.07.2025 20:15
© Copyright Mercedes-Benz AG
CCUSHWA
Note
Page 4 / 4
- 🔥🔥🔥2026 New Functions Making X7HD the Top Dog - Big Surprise!!! ANCEL X7HD truck scanner 10 major functional advantages .✅>Full HDOBD/OBD2 Function ✅>ALL System Diagnostic ✅>42+ Reset Function ✅>Active Test / Bi-Directional Control✅>ECU Coding✅>Graphing Live Data✅>Wide Compatibility ✅>2 Yrs Free Update✅>Remote Operation✅>Bluetooth 5.0 & Wifi In addition, 8 major hardware advantages: ✅>6000 mAh✅>10.1 inch Tablet✅>2G RAM
✅>32G ROM (Expandable to 128GB)✅>Data Record & Replay & Print✅>Android 10.0✅>Bluetooth 5.0 & Wifi✅>14 Languages - 🚛OEM DPF Forced Regen & Cylinder Cutout Test & more - ANCEL X7HD diesel scanner diagnostic tool not only supports DPF regeneration, DPF reset, DPF related information reset, DPR state reset, DPD forced regeneration etc, which helps you better solve the exhaust aftertreatment system problems, but also supports activate motor to do exhaust air in ABS Automatically. Moreover, it features TPMS activation, cylinder cut-off and learning functions
- 🚛Advanced ECU Coding & Programming - ANCEL X7HD 10.1inch truck scanner diagnostic tool is equipped with advanced ECU coding, supports Level calibration, Idle speed learning and Adjustment, Camshaft timing control learning, Control unit adaptations, Injector Codes, Read/Write VIN, Road speed limit optional vehicle speed set, etc... PLEASE NOTE that ECU codes are not compatible with all vehicles, please send us your VIN# to check vehicle compatibility
- 🚛42+ Reset Functions & Bidirectional Control - 2026 newest top heavy duty truck scan tool, comes with 42+ special services (ECU, Speed Limit and Idle Reset, Oil Reset, Injector Coding, EPB, ABS, SRS, Suspension, Throttle, etc. and always keep growing), which meet all your various needs for service and maintenance
- 🚛10 Inch All Systems Diesel Scanner & Full HDOBD/OBD2 Modes - ANCEL X7HD diesel truck scan tool supports all systems scan, such as Engine, Brake, Retarder, TECU Transmission, Tachograph, ABS, SRS, TPMS, EPB, SAS, ESP, and other vehicle systems, comes with 10 obd2 service modes: read/erase error codes, Data Stream, I/M Readiness, Vehicle Information, Actuations, DTC Lookup, EVAP, view freeze frame, etc
- 【Extensive Compatibility】HD601 heavy duty truck scanner supports 12V & 24V commercial vehicles and all major truck models that comply with standard protocols (SAE J1939, SAE J1708, ISO 14230-4, ISO 15765-4 and ISO 9141-2, ISO 27145-4 and Euro6). Fits for Cummins, Paccar, Detroit, Caterpillar, Freightliner, International, Peterbilt, Ford Heavy Truck, Class 4-Class 8 trucks, etc. It also supports engine diagnosis on most cars, minivans, light trucks and pickups
- 【 Full System Diagnostic】HD601 Diesel Scanner supports all system scans of heavy trucks compliant with standard protocols SAE J1939 & J1708, such as Engine, ABS, Transmission, Braking System, ESP, EPS, Fuel System, etc, It is a great scan tool for Cummins, Caterpillar, Detroit, Caterpillar, Maxxforce, Bendix,Wabash, Wabaco, Haldex, Allison, Eaton heavy trucks, With this truck tool, you can get deep analysis data about the system and do some repairs by yourself, saving much time and money. Note: Only heavy truck vehicles that comply with the above protocol can diagnose the entire system
- 【Enhanced Diesel OBD Scanner】The HD601 Diesel OBD Scanner offers unparalleled diagnostic capabilities for heavy-duty trucks. Beyond code reading, clearing, and live data display, it retrieves vehicle information, freeze frames, and DTCs. With 6, 9, and 16 pin cables, it ensures compatibility with various engines. This scanner's real-world testing prowess ensures comprehensive support for a wide array of heavy-duty truck engines, making it an indispensable tool for truck diagnostics
- 【DTC Library】+【Life Time Free Update】The built-in DTC library allows you to retrieve the codes directly without searching for the definition in the book. Whether you are a professional mechanic or a DIY car owner, HD601 diesel scanner explains the existing problem, makes it easier for you to understand code definitions and helps you locate vehicle faults. Note: This device cannot directly solve the fault. Plus, you get a lifetime free internet updates, so you always have the latest software for diagnostics in English and Spanish languages.
- 【Friendly Design, Easy of Use】This scanner is plug and play, simple and convenient, and very friendly for beginners. With improved buttons for easy menu navigation. The excellent 2.8 inch LCD color screen makes it easy to view the displayed results and gives you a better overview of your car's problem areas and the identified codes. In addition, the processor is super-fast and responds without lagging, providing maximum comfort and efficiency in diagnostic and service work
- Why NEXAS NL102 Truck Scan Tool? The NL102 outshines other truck scanner with its extensive diagnostic features. It offers full system diagnostics for major trucks meeting standard protocols, along with complete OBD2 functionality. Beyond read fault codes, clear codes and live data display, it enables vehicle info retrieval, freeze frame capture, and DTC lookup. Equipped with 6-pin, 9-pin, 16-pin connectors, it ensures broad truck compatibility. Plus, enjoy lifetime free updates in English, Spanish, and French, keeping your diagnostic scanner software current.
- Wide Compatibility - Friendly Reminder: To avoid compatibility issues, please confirm with us via Amazon Messages before purchasing. This heavy duty truck scanner is compatible with all heavy-duty trucks and semi that adhere to standard protocols (J1587, J1939, J1708). It covers a wide range of vehicle models, including Cummins, Detroit, Caterpillar, Freightliner, International, Kenworth, John Deere, Peterbilt, Sterling, Mack, Paccar, Western Star, Mercedes-Benz, Volvo, Scania, MAN, Renault, ERF, Foden, Seddon-Atkinson, Iveco, DAF, SISU, STEYR, ISUZU etc. Equipped with 6-pin, 9-pin, and 16-pin connectors for versatile device compatibility, ensuring stable plug-and-play connections.
- Save Hundreds of Money for All Heavy Duty Trucks – This diesel diagnostic scanner supports accurate full-system scans for all heavy-duty trucks that comply with standard protocols (J1587, J1939, and J1708). It can read and clear trouble codes across a range of vehicle systems, including the engine, transmission, instrument panel, drivetrain, brake system, suspension, ABS, ESP, EPS, fuel system, etc. The truck scanner communicates directly with your truck's computer to provide real-time data stream analysis, letting you pinpoint issues with precision. This cuts down on waste from unnecessary part replacements, saving you time and hundreds or even thousands of dollars.
- All OBD2 Functions + Battery Health Monitoring – Unlike many obd2 scanners on the market that only cover partial OBD2 features, ours gives you full OBD2 capability: read & clear codes, live data, freeze frame data, I/M readiness checks, EVAP tests, on-board monitor, O2 sensor tests, vehicle info, and DTC lookup. That means more detailed insights for pros and DIYers alike. The NL102 isn't just a code scanner – it's a battery saver. Regularly check your car's battery health, and catch issues before it dies completely. No more unexpected no-starts in the driveway or on the road. It diagnoses battery condition accurately, helping you avoid costly last-minute repairs.
- Plug and Play & One-click for DTC: NEXAS diesel scanner is user-friendly. It comes with an intuitive screen and easy-to-understand interface, making it accessible even for non-professionals to get started. And the built-in DTC library in the code reader allows you to directly retrieve codes without searching for definitions in books, making it easier to understand the code definitions and solve problems more quickly.
This product presentation was made with AAWP plugin.
Last update on 2026-05-11 / Affiliate links / Images from Amazon Product Advertising API