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Mercedes-Benz U142791

"Implausible data were received from the control unit 'Head unit'. The parameter is outside the permissible range." Cause Under Determination. Remedy Update vehicle software to MB

DriveNot yet established by verified evidence. One Mercedes-Benz communication states that, before the stated software-availability date, the vehicle can be released after the cluster message is cleared at startup; this does not establish general driving safety or applicability outside that bulletin condition.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Mercedes-Benz service provider and provide DTC U142791 plus the exact cluster warning message. Ask the provider to review LI54.71-P-080653 and confirm MB.OS version 1.3.10 applicability.
Confidence95%

Quick answer

For certain 2026–2027 US Mercedes-Benz CLA-Class vehicles, DTC U142791 has been documented with a driver-assistance warning and an active/stored fault in the N62/5 driver assistance control unit. Mercedes-Benz service communications direct dealers to update MB.OS to version 1.3.10 and recheck the concern after a bus-sleep period.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does U142791 mean?

For certain 2026–2027 US Mercedes-Benz CLA-Class vehicles, DTC U142791 has been documented with a driver-assistance warning and an active/stored fault in the N62/5 driver assistance control unit. Mercedes-Benz service communications direct dealers to update MB.OS to version 1.3.10 and recheck the concern after a bus-sleep period.

2. Technical explanation

U142791 means: “Implausible data were received from the control unit ‘Head unit’. The parameter is outside the permissible range.” The listed cause is under determination. Verified Mercedes-Benz communications associate this DTC with an active and stored entry in the N62/5 driver assistance control unit processor, in the specific condition described by the bulletin.

3. What system is affected?

Verified evidence identifies the N62/5 driver assistance control unit processor and communication data received from the head unit. A broader system classification is not yet established by verified evidence.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • The instrument cluster may consistently display: “Driver Assistance System Functions Limited Please Drive with Caution See Operator's Manual” at every key cycle.
  • The N62/5 driver assistance control unit processor may contain active and stored DTC U142791.

6. Possible causes

  • The cause is under determination.
  • The verified service communications address the condition with an MB.OS software update to version 1.3.10.

7. Can I still drive the vehicle?

Not yet established by verified evidence. One Mercedes-Benz communication states that, before the stated software-availability date, the vehicle can be released after the cluster message is cleared at startup; this does not establish general driving safety or applicability outside that bulletin condition.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Confirm the exact instrument-cluster message. The service communication cautions that other white ADAS cluster-message variants exist.
  • Arrange diagnosis with an authorized Mercedes-Benz service provider if the exact warning and U142791 are present.
  • Do not attempt high-voltage or control-unit repair procedures yourself.

10. Step-by-step troubleshooting

  1. A Mercedes-Benz technician can verify the MB.OS version through A26/17 in Xentry under Version or through VeDoc vehicle information for control units.
  2. For the documented condition, the service instruction is to update MB.OS to 1.3.10, perform a 30-minute bus sleep, and recheck for the cluster message.
  3. If the message clears and the concern is resolved, the communication directs release of the vehicle.
  4. If the condition remains after the update, the communication directs the dealer to open a TIPS case to the Body, Chassis, and Entertainment inbox.

11. When to contact service

Contact an authorized Mercedes-Benz service provider and provide DTC U142791 plus the exact cluster warning message. Ask the provider to review LI54.71-P-080653 and confirm MB.OS version 1.3.10 applicability.

12. What the service center may check

  • Verify that the cluster warning exactly matches the documented message.
  • Check for active and stored U142791 in the N62/5 driver assistance control unit processor.
  • Verify the installed MB.OS version.
  • Update to MB.OS 1.3.10 when applicable.
  • After the update, allow a 30-minute bus sleep and recheck the cluster message.

13. Possible repair or resolution

  • Mercedes-Benz communications identify an update to MB.OS 1.3.10 as the service action for the documented condition.
  • If the warning clears and the concern is resolved after the update and recheck, the vehicle may be released per the communication.
  • If unresolved after the update, dealer escalation through a TIPS case is directed.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mercedes-Benz LI54.71-P-080653, reported to NHTSA as Manufacturer Communications 11032968, 11033176, 11033757, and 11033805. The June 11, 2026 communication states that MB.OS 1.3.10 is available and directs escalation if the concern persists after updating.

16. Recall information

  • No recall information was supplied in the verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Mercedes-Benz manufacturer communications: https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11033805

19. Frequently asked questions

What does U142791 mean?

It indicates that implausible data were received from the head unit and that a parameter was outside the permissible range. The listed cause is under determination.

Which vehicles are covered by the supplied evidence?

The applicability data identifies US-market Mercedes-Benz CLA-Class vehicles for model years 2026–2027, with one additional 2026 entry. Exact VIN-level applicability is not established by the supplied evidence.

What warning is associated with this bulletin?

The documented warning is: “Driver Assistance System Functions Limited Please Drive with Caution See Operator's Manual.” The bulletin says to verify the message exactly because other white ADAS messages exist.

What is the documented remedy?

For the documented condition, Mercedes-Benz directs an MB.OS update to version 1.3.10, followed by a 30-minute bus sleep and a recheck for the cluster message.

Can I continue driving?

Not yet established by verified evidence. Follow the displayed warning and seek authorized Mercedes-Benz service assessment.

20. Sources & verification

Verified
Mercedes-Benz U142791: "Implausible data were received from the… | EV Diagnostics