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Mercedes-Benz P0E5400

As a consequence, on vehicles with BMS30EB02, the DTC for the auxiliary assembly fuse P0E2F00 can be set. This triggers the yellow HV drive system warning message. In the ignition

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Mercedes-Benz service provider for diagnosis, particularly if 12 V or HV warning messages are displayed. The supplied evidence does not establish an owner-performed repair.
Confidence95%

Quick answer

For verified U.S. 2022–2025 Mercedes-Benz EQB and G-Class applicability, P0E5400 is documented in Mercedes-Benz service communication LI54.10-P-079533 as one of several DTCs that may be stored by the DC/DC converter. The communication describes associated 12 V, HV, and instrument-cluster warning messages; it does not establish a standalone code definition, driving status, charging status, or a specific repair for P0E5400 alone.

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 P0E5400 mean?

For verified U.S. 2022–2025 Mercedes-Benz EQB and G-Class applicability, P0E5400 is documented in Mercedes-Benz service communication LI54.10-P-079533 as one of several DTCs that may be stored by the DC/DC converter. The communication describes associated 12 V, HV, and instrument-cluster warning messages; it does not establish a standalone code definition, driving status, charging status, or a specific repair for P0E5400 alone.

2. Technical explanation

Official NHTSA-posted Mercedes-Benz service communications identify P0E5400 within a DC/DC-converter fault-code group: P0C3B00, P0E9700, P0E5400, and P0C4000. The documents state that not every DTC in a group is necessarily triggered. They also identify a second group that may be stored: P1D0B00, P1CA000, and U011500. On vehicles with BMS30EB02, P0E2F00 for the auxiliary assembly fuse can be set as a consequence, and this triggers a yellow HV drive-system warning message. The supplied evidence does not establish that P0E5400 itself means an auxiliary-fuse fault.

3. What system is affected?

DC/DC converter; the supplied official communication also references the 12 V battery message, HV warnings, instrument cluster, BMS30EB02, and the auxiliary assembly fuse DTC P0E2F00.

4. How serious is this code?

Not yet established by verified evidence. The official communication does state that, if initial warning messages are ignored in the same ignition cycle, additional warnings may be displayed, including a red HV warning message and a yellow HV drive-system warning message.

5. Symptoms you may notice

  • A red 12 V battery message is described in the official communication.
  • A white HV warning message is described in the official communication.
  • A warning message in the instrument cluster is described in the official communication.
  • If initial warnings are ignored in the same ignition cycle, a red HV warning message and a yellow HV drive-system warning message may be displayed.
  • For vehicles with BMS30EB02, P0E2F00 may be set and triggers a yellow HV drive-system warning message.

6. Possible causes

  • The verified evidence associates P0E5400 with a DC/DC-converter fault-code group.
  • A specific root cause of P0E5400 is not yet established by verified evidence.
  • The evidence states that P0E2F00 may be set as a consequence on vehicles with BMS30EB02; it does not establish P0E2F00 as the cause of P0E5400.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Do not ignore displayed warning messages in the same ignition cycle, because the official communication states that additional warning messages may then be displayed.
  • Arrange diagnosis by an authorized Mercedes-Benz service provider. No high-voltage repair procedure is established by the supplied evidence.

10. Step-by-step troubleshooting

  1. Have the DC/DC converter checked for the documented DTC group: P0C3B00, P0E9700, P0E5400, and P0C4000.
  2. Have the service provider check whether DTCs from the second documented group are also present: P1D0B00, P1CA000, and U011500.
  3. For a vehicle with BMS30EB02, have the service provider check whether P0E2F00 is present.
  4. The official communication states that some DTCs in a listed group may not be triggered.

11. When to contact service

Contact an authorized Mercedes-Benz service provider for diagnosis, particularly if 12 V or HV warning messages are displayed. The supplied evidence does not establish an owner-performed repair.

12. What the service center may check

  • Retrieve and evaluate DC/DC-converter fault memory for the documented DTC groups.
  • Check for the documented warning-message sequence in the instrument cluster.
  • Determine whether the vehicle has BMS30EB02 and whether P0E2F00 is stored.

13. Possible repair or resolution

  • Not yet established by verified evidence. The supplied excerpts identify an official Mercedes-Benz service communication but do not provide its repair procedure or resolution.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mercedes-Benz LI54.10-P-079533, published through NHTSA Manufacturer Communications 11021800 (2025-08-08), 11021970 (2025-08-05), 11023154 (2025-09-16), 11028815 (2026-02-14), and 11029977 (2026-03-11).
  • The communication documents P0E5400 as part of a DC/DC-converter DTC group and describes related warning-message behavior.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official source: NHTSA-posted Mercedes-Benz Manufacturer Communication LI54.10-P-079533. https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2025-2026.zip#nhtsa_id=11021800

19. Frequently asked questions

What does P0E5400 mean on a Mercedes-Benz EV?

The supplied official evidence does not provide a standalone definition. It identifies P0E5400 as one of several DTCs that may be stored by the DC/DC converter.

Can P0E5400 appear with other codes?

Yes. The official communication lists P0C3B00, P0E9700, P0E5400, and P0C4000 as one group, and P1D0B00, P1CA000, and U011500 as another group. It also states that not all DTCs in a group are necessarily triggered.

Does P0E5400 cause the yellow HV drive-system warning?

Not established for P0E5400 alone. The official communication specifically states that P0E2F00 can be set on vehicles with BMS30EB02 and that P0E2F00 triggers the yellow HV drive-system warning message.

Which vehicles are covered by the supplied verified applicability data?

U.S.-market 2022–2025 Mercedes-Benz EQB and G-Class vehicles.

20. Sources & verification

Verified
Mercedes-Benz P0E5400: As a consequence, on vehicles with BMS30EB02,… | EV Diagnostics