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Mercedes-Benz B15CE00

control unit for telematics services (HERMES)": • The message "SOS - service not activated" permanently lights up in the instrument cluster AND the actual value "Error when replaci

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceContact an authorized Mercedes-Benz service provider, particularly if the condition followed replacement of the HERMES or RAMSES telematics-services control unit.
Confidence95%

Quick answer

B15CE00 is documented by Mercedes-Benz as a telematics-services control-unit (HERMES) condition that can occur after replacement of the HERMES or RAMSES telematics control unit, when Digital Extras (formerly Mercedes me) cannot be activated. For HERMES-equipped vehicles, the instrument cluster may permanently display “SOS - service not activated,” with actual value “Error when replacing certificate (CEP.36).”

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 B15CE00 mean?

B15CE00 is documented by Mercedes-Benz as a telematics-services control-unit (HERMES) condition that can occur after replacement of the HERMES or RAMSES telematics control unit, when Digital Extras (formerly Mercedes me) cannot be activated. For HERMES-equipped vehicles, the instrument cluster may permanently display “SOS - service not activated,” with actual value “Error when replacing certificate (CEP.36).”

2. Technical explanation

Verified Mercedes-Benz manufacturer communications LI82.85-P-078473 describe B15CE00 as active or active+saved after replacement of N112/9, the telematics-services control unit (HERMES), or N112/2, the telematics-services control unit (RAMSES). The documented complaint is that Digital Extras, previously Mercedes me, cannot be activated. For HERMES, the bulletin identifies a permanent “SOS - service not activated” message and the activation-status registration actual value “Error when replacing certificate (CEP.36).” The supplied evidence does not establish a broader technical fault mechanism, component failure, or repair procedure.

3. What system is affected?

Telematics services / Digital Extras (previously Mercedes me), including the HERMES telematics-services control unit (N112/9).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Digital Extras (previously Mercedes me) cannot be activated after replacement of the HERMES or RAMSES telematics control unit.
  • DTC B15CE00 is active or active+saved.
  • For HERMES: “SOS - service not activated” permanently lights in the instrument cluster.
  • For HERMES: activation-status registration actual values show “Error when replacing certificate (CEP.36).”

6. Possible causes

  • The verified bulletin documents this condition after replacement of the N112/9 HERMES or N112/2 RAMSES telematics-services control unit.
  • A further root cause is not yet established by verified evidence.

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

  • Record whether B15CE00 is active or active+saved.
  • Note whether the “SOS - service not activated” message is permanently displayed.
  • Have a Mercedes-Benz service provider evaluate the telematics/Digital Extras activation condition.
  • Do not attempt high-voltage repairs; no high-voltage repair is described by the verified evidence.

10. Step-by-step troubleshooting

  1. Verify whether the HERMES or RAMSES telematics-services control unit was replaced before the condition began.
  2. For HERMES, inspect the documented activation-status registration actual value for “Error when replacing certificate (CEP.36).”
  3. Confirm whether Digital Extras can be activated and whether B15CE00 is active or active+saved.
  4. Further diagnostic steps are not yet established by verified evidence.

11. When to contact service

Contact an authorized Mercedes-Benz service provider, particularly if the condition followed replacement of the HERMES or RAMSES telematics-services control unit.

12. What the service center may check

  • Determine whether N112/9 HERMES or N112/2 RAMSES was replaced.
  • Check whether B15CE00 is active or active+saved.
  • For HERMES, check for the permanent “SOS - service not activated” message.
  • For HERMES, check activation-status registration actual values for “Error when replacing certificate (CEP.36).”

13. Possible repair or resolution

  • A specific repair resolution is not included in the supplied verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Mercedes-Benz LI82.85-P-078473, reported through NHTSA Manufacturer Communication 11008880, published October 3, 2024.
  • Mercedes-Benz LI82.85-P-078473, reported through NHTSA Manufacturer Communication 11010755, published November 20, 2024.

16. Recall information

  • No recall information was supplied in the verified evidence.

17. Official manufacturer information

Official NHTSA-hosted Mercedes-Benz manufacturer communications: 11008880 and 11010755, both identifying LI82.85-P-078473.

19. Frequently asked questions

What does B15CE00 mean?

The verified Mercedes-Benz bulletin associates B15CE00 with a post-replacement telematics activation condition involving the HERMES or RAMSES telematics-services control unit, where Digital Extras cannot be activated.

Why does the cluster show “SOS - service not activated”?

For HERMES-equipped vehicles, the verified bulletin documents this message together with B15CE00 and the actual value “Error when replacing certificate (CEP.36)” after the described telematics control-unit replacement condition.

Is it safe to drive or charge?

Not yet established by verified evidence.

Which vehicles are listed in the supplied applicability data?

US-market Mercedes-Benz EQB, EQE, and EQS model years 2022 through 2025 are listed. Some entries end at 2024, while others extend through 2025.

20. Sources & verification

Verified
Mercedes-Benz B15CE00: control unit for telematics services (HERMES)":… | EV Diagnostics