Mercedes-Benz High -voltage electrical system fault
High -voltage electrical system fault
Common search variants: High-voltage electrical system fault · Search ignores case and common separators.
Quick answer
For certain 2022 US Mercedes-Benz EQS-Class vehicles (297 platform), this alert can be associated with powertrain control unit software that does not correspond to current product specifications. The vehicle may fail to enter READY mode and may not start. Mercedes-Benz’s stated remedy is a dealer software update.
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 High -voltage electrical system fault mean?
For certain 2022 US Mercedes-Benz EQS-Class vehicles (297 platform), this alert can be associated with powertrain control unit software that does not correspond to current product specifications. The vehicle may fail to enter READY mode and may not start. Mercedes-Benz’s stated remedy is a dealer software update.
2. Technical explanation
Verified NHTSA manufacturer communication 10210923 (SC-2022030031), published April 8, 2022, states that on affected 2022 EQS-Class vehicles, powertrain control unit software may not correspond to current product specifications. The communication identifies “High-voltage electrical system fault” as one of the instrument-cluster warning messages that may be displayed. It also states that the vehicle may not enter READY mode; if this occurs, the vehicle would not start.
3. What system is affected?
High-voltage electrical system alert; the verified manufacturer communication identifies the powertrain control unit software as the subject of the service campaign.
4. How serious is this code?
Unknown. The supplied diagnostic record does not establish a severity rating. However, the verified communication states that the vehicle may not enter READY mode and may not start.
5. Symptoms you may notice
- Instrument-cluster message: “High-voltage electrical system fault.”
- The vehicle may not enter READY mode.
- If the vehicle does not enter READY mode, it would not start.
- Other example warnings listed in the communication include “Towing prohibited,” a battery symbol with “Fault,” and an error message about the 12V battery.
6. Possible causes
- For covered 2022 EQS-Class vehicles, the powertrain control unit software may not correspond to current product specifications.
- Other causes are 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
- Arrange assessment by an authorized Mercedes-Benz dealer, particularly if the vehicle will not enter READY mode or will not start.
- Do not attempt high-voltage system repair yourself.
10. Step-by-step troubleshooting
- Check whether the vehicle enters READY mode.
- Record the exact instrument-cluster message shown.
- Have an authorized Mercedes-Benz dealer determine whether service campaign SC-2022030031 applies to the vehicle.
11. When to contact service
Contact an authorized Mercedes-Benz dealer to check campaign applicability and perform the specified software update where applicable.
12. What the service center may check
- Verify whether the vehicle is a 2022 Mercedes-Benz EQS-Class on the 297 platform in the US.
- Check whether service campaign SC-2022030031 applies.
- Assess the powertrain control unit software and update it as specified by Mercedes-Benz.
13. Possible repair or resolution
- The verified manufacturer communication states that an authorized Mercedes-Benz dealer will update the powertrain control unit software.
- No other repair resolution is established by the supplied evidence.
14. Affected vehicles
- Mercedes-Benz EQS · 2022 · US
15. Related TSBs / service bulletins
- NHTSA Manufacturer Communication 10210923: SC-2022030031, published April 8, 2022. It describes a service campaign for certain 2022 EQS-Class (297 platform) vehicles in which powertrain control unit software may not correspond to current product specifications. Mercedes-Benz’s stated action is a powertrain control unit software update by an authorized dealer.
16. Recall information
- Not yet established by verified evidence. The supplied source identifies a service campaign, not a recall.
17. Official manufacturer information
Official source: NHTSA Manufacturer Communication 10210923, SC-2022030031: https://static.nhtsa.gov/odi/ffdd/tsbs/TSBS_RECEIVED_2020-2024.zip#nhtsa_id=10210923
19. Frequently asked questions
What does “High-voltage electrical system fault” mean on a 2022 Mercedes-Benz EQS?
For vehicles covered by NHTSA Manufacturer Communication 10210923, it may be one of the warnings associated with powertrain control unit software that does not correspond to current product specifications.
Can this message prevent the EQS from starting?
Yes. The verified communication states that the vehicle may not enter READY mode and, if this occurs, the vehicle would not start.
What is the documented repair?
Mercedes-Benz states that an authorized dealer will update the powertrain control unit software.
Does this apply to every Mercedes-Benz EQS?
No. The supplied applicability evidence is limited to 2022 Mercedes-Benz EQS vehicles in the US. Exact vehicle eligibility should be confirmed by an authorized Mercedes-Benz dealer.