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Tesla UMC_a014

Wall plug adapter error - Charge rate reduced Plug adapter fully into Mobile Connector and retry

Common search variants: UMCa014 · UMC-a014 · UMC a014 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging is indicated as available at a reduced current of 8 A while this alert is present. Whether charging can continue in an individual case is not otherwise established by verified evidence.
ServiceWhether Tesla Service is required is not yet established by verified evidence.
Confidence95%

Quick answer

UMC_a014 means the Tesla Mobile Connector cannot communicate with its wall plug adapter. Charging current is automatically reduced to 8 A. Fully insert the wall plug adapter into the Mobile Connector and retry.

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_a014 mean?

UMC_a014 means the Tesla Mobile Connector cannot communicate with its wall plug adapter. Charging current is automatically reduced to 8 A. Fully insert the wall plug adapter into the Mobile Connector and retry.

2. Technical explanation

The verified Tesla owner-manual material filed with NHTSA describes UMC_a014 as a wall plug adapter error. The Mobile Connector cannot identify the type of wall outlet because it cannot communicate with the attached wall plug adapter; it therefore automatically reduces charge current to 8 A.

3. What system is affected?

Tesla Mobile Connector and its wall plug adapter.

4. How serious is this code?

Severity is not yet established by verified evidence. The verified evidence establishes reduced charging current.

5. Symptoms you may notice

  • The vehicle displays UMC_a014: “Wall plug adapter error - Charge rate reduced.”
  • Mobile Connector charge current is automatically reduced to 8 A.

6. Possible causes

  • The Mobile Connector is unable to communicate with the wall plug adapter.
  • The verified material instructs that the wall plug adapter should be fully inserted into the Mobile Connector; other 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?

Charging is indicated as available at a reduced current of 8 A while this alert is present. Whether charging can continue in an individual case is not otherwise established by verified evidence.

9. What you can safely do

  • Fully insert the wall plug adapter into the Mobile Connector and retry.
  • Refer to the Mobile Connector owner’s manual for troubleshooting of Mobile Connector status lights and charging issues.
  • Use a Tesla Supercharger or Destination Charging location if needed; the verified owner-manual material states these can be located using the vehicle touchscreen map.

10. Step-by-step troubleshooting

  1. Fully seat the wall plug adapter in the Mobile Connector, then retry charging.
  2. Consult the applicable 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

  • Fully inserting the wall plug adapter into the Mobile Connector and retrying is the verified instructed action. Further repair resolution is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA manufacturer communications containing Tesla owner-manual guidance document UMC_a014, including MC-10253666 (published March 27, 2024): https://static.nhtsa.gov/odi/tsbs/2024/MC-10253666-9999.pdf
  • NHTSA manufacturer communication MC-10250484 (published December 1, 2023) describes the Mobile Connector’s inability to communicate with the wall plug adapter and the automatic reduction to 8 A: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-filed Tesla owner-manual guidance: https://static.nhtsa.gov/odi/tsbs/2024/MC-10253666-9999.pdf

19. Frequently asked questions

What does Tesla UMC_a014 mean?

It means the Mobile Connector cannot communicate with the wall plug adapter, so it cannot identify the wall-outlet type and automatically reduces charge current to 8 A.

What should I do when UMC_a014 appears?

Fully insert the wall plug adapter into the Mobile Connector and retry.

Why is charging slower with UMC_a014?

The verified guidance states that charging current is automatically reduced to 8 A when the Mobile Connector cannot communicate with the wall plug adapter.

Can I drive with UMC_a014?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla UMC_a014: Wall plug adapter error - Charge rate reduced Plug… | EV Diagnostics