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Mercedes-Benz FC151E29- The level sensor at front left has a malfunction. There is an invalid si- gnal

FC151E29- The level sensor at front left has a malfunction. There is an invalid si- gnal

Common search variants: FC151E29- The level sensor at front left has a malfunction. There is an invalid signal · Search ignores case and common separators.

DriveYes, based on one official Mercedes-Benz communication stating that the concern does not impact vehicle drivability.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Mercedes-Benz service center. Provide FC151E29 and the exact instrument-cluster message. The verified communications describe software updates as the remedy.
Confidence90%

Quick answer

For applicable U.S. 2024–2025 Mercedes-Benz EQE vehicles, FC151E29 is associated with an invalid front-left level-sensor signal processed by the HLI/LED headlamp range-adjustment system. Mercedes-Benz communications link it to messages that adaptive high-beam assistance is unavailable/inoperative or DIGITAL LIGHT has reduced functionality. The documented remedy is a control-unit software update, not parts replacement.

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 FC151E29- The level sensor at front left has a malfunction. There is an invalid si- gnal mean?

For applicable U.S. 2024–2025 Mercedes-Benz EQE vehicles, FC151E29 is associated with an invalid front-left level-sensor signal processed by the HLI/LED headlamp range-adjustment system. Mercedes-Benz communications link it to messages that adaptive high-beam assistance is unavailable/inoperative or DIGITAL LIGHT has reduced functionality. The documented remedy is a control-unit software update, not parts replacement.

2. Technical explanation

Verified Mercedes-Benz technical communications describe FC151E29 in the HLI control unit or the front-left HLI/LED headlamp range-adjustment control unit. Documented explanations include HLI control-unit processing of level-sensor data, older HLI software releases, and electronic interference at the front-axle sensor level. Depending on the bulletin version and vehicle configuration, Mercedes-Benz specifies updating the HLI/LED headlamp range-adjustment control units, starting with the front-left/left controller. One communication also specifies SCN coding of the EZS after the updates and use of software item number A2239027738 or newer. Parts replacement is specifically stated not to resolve the complaint in the LI82.10-P-078470 communications.

3. What system is affected?

HLI/LED headlamp range-adjustment system, including the front-left level-sensor signal and HLI control unit(s).

4. How serious is this code?

Not yet established by verified evidence. One official communication states that this concern does not impact vehicle drivability.

5. Symptoms you may notice

  • Instrument-cluster message: “Adaptive high beams assistant not available/inoperative.”
  • Instrument-cluster message: “DIGITAL LIGHT reduced range of functions.”

6. Possible causes

  • Older HLI control-unit software release.
  • HLI control-unit processing of level-sensor data.
  • Electronic interference occurring at the front-axle sensor level.

7. Can I still drive the vehicle?

Yes, based on one official Mercedes-Benz communication stating that the concern does not impact vehicle drivability.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Arrange diagnosis with an authorized Mercedes-Benz service center and provide fault code FC151E29.
  • Record any instrument-cluster message, including whether it reports adaptive high-beam assistance unavailable/inoperative or DIGITAL LIGHT reduced functionality.
  • Do not assume replacement of the level sensor, headlamp components, or control units will resolve this specific documented software-related complaint.

10. Step-by-step troubleshooting

  1. Have service personnel confirm whether FC151E29 is stored in the HLI control unit or the front-left HLI/LED headlamp range-adjustment control unit.
  2. Have the vehicle checked against Mercedes-Benz LI82.10-P-078470 and LI82.10-P-079179, as applicable.
  3. Have service personnel verify the applicable HLI/LED headlamp range-adjustment software update procedure.

11. When to contact service

Contact an authorized Mercedes-Benz service center. Provide FC151E29 and the exact instrument-cluster message. The verified communications describe software updates as the remedy.

12. What the service center may check

  • Confirm the applicable vehicle configuration and control-unit version.
  • Check for Mercedes-Benz software updates for the HLI/LED headlamp range-adjustment control units.
  • For LI82.10-P-078470 procedures, update the left/front-left controller first where specified.
  • Where specified by the applicable bulletin, perform SCN coding of the EZS after software updates.
  • Where specified, verify software with item number A2239027738 or newer.

13. Possible repair or resolution

  • Update the HLI control-unit software.
  • Update the HLI/LED headlamp range-adjustment control units, beginning with the front-left/left controller where specified.
  • Parts replacement is not expected to resolve the LI82.10-P-078470 complaint; Mercedes-Benz communications state not to replace parts for that complaint.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mercedes-Benz LI82.10-P-078470; NHTSA Manufacturer Communication 11009138, published October 22, 2024.
  • Mercedes-Benz LI82.10-P-078470; NHTSA Manufacturer Communication 11012804, published January 3, 2025.
  • Mercedes-Benz LI82.10-P-078470; NHTSA Manufacturer Communication 11018297, published May 13, 2025.
  • Mercedes-Benz LI82.10-P-078470; NHTSA Manufacturer Communication 11018365, published May 14, 2025.
  • Mercedes-Benz LI82.10-P-079179; NHTSA Manufacturer Communication 11017208, published April 21, 2025.
  • Mercedes-Benz LI82.10-P-079179; NHTSA Manufacturer Communication 11023024, published September 3, 2025.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified applicability evidence identifies U.S. Mercedes-Benz EQE model-year 2024 and 2024–2025 entries. Official NHTSA-hosted Mercedes-Benz communications: https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11018365

19. Frequently asked questions

What does FC151E29 mean?

It identifies a malfunction with an invalid signal from the front-left level sensor in the documented HLI/LED headlamp range-adjustment context.

Why does the warning appear?

Verified communications identify HLI software/data-processing issues, older HLI software, or electronic interference at the front-axle sensor level.

Will replacing parts fix it?

For the LI82.10-P-078470 complaint, Mercedes-Benz communications state that parts replacement will not resolve the complaint and instruct not to replace parts.

Can I still drive?

One official communication states that this concern does not impact vehicle drivability.

Is there a verified charging restriction?

Not yet established by verified evidence.

20. Sources & verification

Verified
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