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Tesla UMC_a002

Unable to charge - Mobile Connector GFCI tripped Unplug charge handle from charge port and retry

Common search variants: UMCa002 · UMC-a002 · UMC a002 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeThe vehicle cannot charge with the Mobile Connector while this alert is active. Whether charging is available through another charging method is not yet established by verified evidence.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

Tesla alert UMC_a002 means charging cannot continue because the ground-fault circuit interrupter (GFCI) in the Mobile Connector has tripped. Unplug the charge handle from the vehicle charge port and retry charging.

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1. What does UMC_a002 mean?

Tesla alert UMC_a002 means charging cannot continue because the ground-fault circuit interrupter (GFCI) in the Mobile Connector has tripped. Unplug the charge handle from the vehicle charge port and retry charging.

2. Technical explanation

The Mobile Connector contains a GFCI, a protective feature comparable to the GFCI in a wall outlet. Verified Tesla owner-manual material states that this feature is designed to stop the flow of electricity when there is a problem. When UMC_a002 appears, the vehicle cannot charge using that Mobile Connector until the charge handle is unplugged and charging is retried.

3. What system is affected?

Tesla Mobile Connector charging equipment, specifically its ground-fault circuit interrupter (GFCI).

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • The vehicle cannot charge using the Mobile Connector.
  • The vehicle displays UMC_a002: “Unable to charge - Mobile Connector GFCI tripped.”

6. Possible causes

  • The Mobile Connector GFCI has tripped.
  • The specific condition that caused the GFCI to trip 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?

The vehicle cannot charge with the Mobile Connector while this alert is active. Whether charging is available through another charging method is not yet established by verified evidence.

9. What you can safely do

  • Unplug the Mobile Connector charge handle from the vehicle charge port.
  • Retry charging.
  • Refer to the Mobile Connector product owner’s manual for troubleshooting of Mobile Connector status lights and charging issues.

10. Step-by-step troubleshooting

  1. Unplug the charge handle from the charge port and retry charging.
  2. Consult the Mobile Connector product owner’s manual for Mobile Connector status-light and charging-issue troubleshooting.

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

  • Not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10250484 (published 2023-12-01): Tesla owner-manual material documents UMC_a002 and states that the Mobile Connector GFCI has tripped. https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253666 (published 2024-03-27): Tesla owner-manual material includes UMC_a002 and directs users to the product owner’s manual for Mobile Connector status-light and charging-issue troubleshooting. https://static.nhtsa.gov/odi/tsbs/2024/MC-10253666-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla owner-manual communications document this alert for US-market Tesla Model 3 (2013-2024 in the supplied applicability records), Model S (2012-2024), Model X (2016-2024), and Model Y (2020-2024). Applicability records overlap by year; confirm coverage using the vehicle’s own documentation. Most recently verified: 2026-09-23.

19. Frequently asked questions

What does Tesla UMC_a002 mean?

It means the vehicle cannot charge because the GFCI in the Mobile Connector has tripped.

What should I do when UMC_a002 appears?

Unplug the charge handle from the vehicle charge port and retry charging.

Why does the Mobile Connector have a GFCI?

Verified Tesla material states that, like a GFCI in a wall outlet, it is designed to stop the flow of electricity when there is a problem.

Does UMC_a002 prove which component or condition caused the trip?

No. The specific cause of the GFCI trip is not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla UMC_a002: Unable to charge - Mobile Connector GFCI tripped… | EV Diagnostics