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Tesla UMC_a011

Charging equipment communication error Try again or try different equipment

Common search variants: UMCa011 · UMC-a011 · UMC a011 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNo while this alert condition is present: verified owner-manual material states that the vehicle is unable to charge.
ServiceService-required status is unknown in the diagnostic record. Contact Tesla service if the issue persists, but a specific service threshold is not established by verified evidence.
Confidence95%

Quick answer

UMC_a011 means the Tesla cannot charge because it cannot communicate effectively with the Mobile Connector. The Mobile Connector cannot confirm through proximity detection that the charge handle is fully connected to the vehicle.

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 UMC_a011 mean?

UMC_a011 means the Tesla cannot charge because it cannot communicate effectively with the Mobile Connector. The Mobile Connector cannot confirm through proximity detection that the charge handle is fully connected to the vehicle.

2. Technical explanation

Verified Tesla owner-manual material filed with NHTSA describes UMC_a011 as a charging-equipment communication error. The alert specifically concerns communication with the Mobile Connector and its inability to confirm, via proximity detection, that the charge handle is fully connected. The documented result is that the vehicle is unable to charge.

3. What system is affected?

Charging equipment communication involving the Tesla Mobile Connector and charge-handle connection detection.

4. How serious is this code?

The diagnostic record lists severity as unknown. The verified evidence establishes a charging interruption, but does not establish a safety severity classification.

5. Symptoms you may notice

  • The UMC_a011 alert may be displayed.
  • The vehicle is unable to charge.
  • The Mobile Connector cannot confirm that the charge handle is fully connected through proximity detection.

6. Possible causes

  • The vehicle cannot communicate effectively with the Mobile Connector.
  • The Mobile Connector cannot confirm via proximity detection that the charge handle is fully connected to the vehicle.
  • Additional underlying 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?

No while this alert condition is present: verified owner-manual material states that the vehicle is unable to charge.

9. What you can safely do

  • Try charging again.
  • Try different charging equipment.
  • For Mobile Connector status-light troubleshooting and charging issues, refer to the product owner's manual.
  • Tesla owner-manual material identifies Tesla Supercharger or Destination Charging locations as charging alternatives; these can be located using the vehicle touchscreen map.

10. Step-by-step troubleshooting

  1. Confirm that the charge handle is fully connected to the vehicle before attempting charging again.
  2. Try the charging attempt again.
  3. Try different charging equipment.
  4. Consult the Mobile Connector product owner's manual for status-light and charging-issue troubleshooting.
  5. Further troubleshooting details are not yet established by the supplied verified evidence.

11. When to contact service

Service-required status is unknown in the diagnostic record. Contact Tesla service if the issue persists, but a specific service threshold is not established by verified evidence.

12. What the service center may check

  • Verify effective communication between the vehicle and Mobile Connector.
  • Evaluate why the Mobile Connector cannot confirm, through proximity detection, that the charge handle is fully connected.
  • Additional service procedures are not yet established by verified evidence.

13. Possible repair or resolution

  • No specific repair or component replacement is established by the supplied verified evidence.
  • Use of different charging equipment is a documented alternative action.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10250484: Tesla owner-manual material dated 2023-12-01 documents UMC_a011, its meaning, and Mobile Connector troubleshooting reference: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253666: Tesla owner-manual material dated 2024-03-27 includes UMC_a011 information: https://static.nhtsa.gov/odi/tsbs/2024/MC-10253666-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Tesla owner-manual content submitted to NHTSA states that UMC_a011 occurs when the vehicle cannot communicate effectively with the Mobile Connector and the connector cannot confirm via proximity detection that the charge handle is fully connected. Official source example: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf

19. Frequently asked questions

What does Tesla UMC_a011 mean?

It means the vehicle cannot communicate effectively with the Mobile Connector, which cannot confirm via proximity detection that the charge handle is fully connected.

Can the vehicle charge with UMC_a011?

Verified owner-manual material states that the vehicle is unable to charge while this condition is present.

What should I do for UMC_a011?

Try again or try different equipment. Confirm that the charge handle is fully connected, and refer to the Mobile Connector product owner's manual for status-light and charging-issue troubleshooting.

Can I drive with UMC_a011?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla UMC_a011: Charging equipment communication error Try again or… | EV Diagnostics