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Tesla UMC_a019

Mobile Connector to adapter connection hot Maximum charge rate reduced

Common search variants: UMCa019 · UMC-a019 · UMC a019 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeThe Mobile Connector has reduced charge current. Whether charging can continue in a particular situation is not yet established by verified evidence.
ServiceWhether Tesla service is required is not yet established by verified evidence.
Confidence95%

Quick answer

Tesla alert UMC_a019 means the Mobile Connector reduced charge current after detecting a high temperature at the connection between the wall plug adapter and the Mobile Connector control box.

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_a019 mean?

Tesla alert UMC_a019 means the Mobile Connector reduced charge current after detecting a high temperature at the connection between the wall plug adapter and the Mobile Connector control box.

2. Technical explanation

This is a charging-equipment alert, not a vehicle-system fault description. Verified Tesla owner-manual material filed with NHTSA states that the reduced charge rate is caused by a detected high temperature at the wall-plug-adapter-to-control-box connection.

3. What system is affected?

Tesla Mobile Connector, specifically the connection between the wall plug adapter and the Mobile Connector control box.

4. How serious is this code?

The database severity is unknown. Verified evidence establishes that charging current has been reduced.

5. Symptoms you may notice

  • Maximum charge rate is reduced.
  • The UMC_a019 alert is displayed.
  • The Mobile Connector has detected high temperature at the wall plug adapter-to-control-box connection.

6. Possible causes

  • High temperature detected at the connection between the wall plug adapter and the Mobile Connector control box.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

The Mobile Connector has reduced charge current. Whether charging can continue in a particular situation is not yet established by verified evidence.

9. What you can safely do

  • Make sure the wall plug adapter is fully connected to the Mobile Connector control box.
  • For Mobile Connector status-light and charging-issue troubleshooting, refer to the product owner's manual.

10. Step-by-step troubleshooting

  1. Verify that the wall plug adapter is fully connected to the Mobile Connector control box.
  2. Consult the applicable Tesla product owner's manual for Mobile Connector status-light and charging troubleshooting.

11. When to contact service

Whether Tesla service is required is 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 December 1, 2023, contains Tesla owner-manual material for UMC_a019: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • Additional NHTSA-filed Tesla manufacturer communications repeat this owner-manual alert information; the supplied evidence does not establish a repair-specific service bulletin.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-filed Tesla owner-manual material identifies UMC_a019 as “Mobile Connector to adapter connection hot — Maximum charge rate reduced.” The supplied verified sources include: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf

19. Frequently asked questions

What does Tesla UMC_a019 mean?

It means charge current was reduced because the Mobile Connector detected a high temperature at the connection between the wall plug adapter and the control box.

What should I check for UMC_a019?

Tesla's verified owner-manual instruction is to make sure the wall plug adapter is fully connected to the Mobile Connector control box.

Does UMC_a019 mean the vehicle cannot be driven?

Not yet established by verified evidence.

Is a Tesla service visit required?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla UMC_a019: Mobile Connector to adapter connection hot Maximum… | EV Diagnostics