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Tesla UMC_w001

Unable to charge with Mobile Connector Inadequate outlet grounding - Try another outlet

Common search variants: UMCw001 · UMC-w001 · UMC w001 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging with the Mobile Connector at the affected outlet is unavailable. The verified alert instructs the user to try another outlet.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

UMC_w001 means the Tesla Mobile Connector detected insufficient grounding at the electrical outlet. Tesla documentation says this is likely due to an inadequate or missing ground connection and does not indicate a problem with the vehicle or Mobile Connector. Try another outlet.

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1. What does UMC_w001 mean?

UMC_w001 means the Tesla Mobile Connector detected insufficient grounding at the electrical outlet. Tesla documentation says this is likely due to an inadequate or missing ground connection and does not indicate a problem with the vehicle or Mobile Connector. Try another outlet.

2. Technical explanation

The alert text is: “Unable to charge with Mobile Connector — Inadequate outlet grounding — Try another outlet.” Official Tesla owner-manual material filed with NHTSA states that the Mobile Connector detected insufficient outlet grounding, likely caused by an inadequate or missing ground connection. The documented condition points to the outlet rather than the vehicle or Mobile Connector.

3. What system is affected?

External AC electrical outlet grounding during charging with the Tesla Mobile Connector.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • The vehicle displays UMC_w001.
  • Charging with the Mobile Connector is unable to start or continue at the affected outlet.

6. Possible causes

  • The electrical outlet has insufficient grounding.
  • An inadequate ground connection at the outlet.
  • A missing ground connection at the outlet.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Charging with the Mobile Connector at the affected outlet is unavailable. The verified alert instructs the user to try another outlet.

9. What you can safely do

  • Try another outlet, as directed by the alert.
  • Do not treat this alert as evidence of a vehicle or Mobile Connector fault; Tesla documentation attributes it to the outlet grounding condition.

10. Step-by-step troubleshooting

  1. Use a different outlet with the Mobile Connector.

11. When to contact service

Not yet established by verified evidence.

12. What the service center may check

  • Not yet established by verified evidence.

13. Possible repair or resolution

  • Use an outlet that does not produce the inadequate-grounding alert. Further repair resolution is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Official Tesla owner-manual material submitted to NHTSA documents UMC_w001 and explains that it indicates insufficient electrical-outlet grounding, likely due to an inadequate or missing ground connection. Example: NHTSA Manufacturer Communication 10250483 (published December 1, 2023): https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified applicability: US Tesla Model 3 (2017–2023); Model S (2012–2023); and Model X (2016–2023). Verified source: Tesla owner-manual content filed with NHTSA, including https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf.

19. Frequently asked questions

What does Tesla alert UMC_w001 mean?

It means the Mobile Connector detected insufficient grounding at the electrical outlet, likely from an inadequate or missing ground connection.

Is UMC_w001 a vehicle or Mobile Connector fault?

Tesla documentation states that this alert does not indicate an issue with the Mobile Connector or vehicle; it points to the electrical outlet.

What should I do when UMC_w001 appears?

Try another outlet, as stated in the alert.

Which vehicles are verified as applicable?

US Model 3 (2017–2023), Model S (2012–2023), and Model X (2016–2023).

20. Sources & verification

Verified
Show all 24 verified sources
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