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Tesla UMC_w014

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

Common search variants: UMCw014 · UMC-w014 · UMC w014 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging is indicated as reduced to 8A. The diagnostic record does not establish a general safe-to-charge determination.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

UMC_w014 means the Tesla Mobile Connector cannot communicate with its wall plug adapter. Charging current is automatically reduced to 8A. 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_w014 mean?

UMC_w014 means the Tesla Mobile Connector cannot communicate with its wall plug adapter. Charging current is automatically reduced to 8A. Fully insert the wall plug adapter into the Mobile Connector and retry.

2. Technical explanation

Verified Tesla owner-documentation evidence states that this alert occurs when the Mobile Connector is unable to communicate with the wall plug adapter. Since it cannot identify the type of wall outlet connected through that adapter, it automatically reduces charge current to 8A.

3. What system is affected?

Tesla Mobile Connector and its wall plug adapter.

4. How serious is this code?

The diagnostic record lists severity as unknown. Verified evidence establishes reduced charging current to 8A, but does not establish a broader severity classification.

5. Symptoms you may notice

  • The vehicle displays UMC_w014: “Wall plug adapter error - Charge rate reduced.”
  • Mobile Connector charging current is automatically reduced to 8A.
  • The Mobile Connector is unable to communicate with the wall plug adapter.

6. Possible causes

  • The Mobile Connector is unable to communicate with the wall plug adapter.
  • Not yet established by verified evidence: the specific reason communication is unavailable.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Charging is indicated as reduced to 8A. The diagnostic record does not establish a general safe-to-charge determination.

9. What you can safely do

  • Fully insert the wall plug adapter into the Mobile Connector and retry.
  • For Mobile Connector status-light and charging-issue troubleshooting, refer to the product owner’s manual.

10. Step-by-step troubleshooting

  1. Fully insert the wall plug adapter into the Mobile Connector and retry.
  2. If the alert remains, consult the Tesla Mobile Connector owner’s manual for status-light and charging guidance.

11. When to contact service

Not yet established by verified evidence.

12. What the service center may check

  • Not yet established by verified evidence beyond confirming that the Mobile Connector is unable to communicate with the wall plug adapter.

13. Possible repair or resolution

  • Fully inserting the wall plug adapter into the Mobile Connector and retrying is the verified instructed action.
  • Not yet established by verified evidence: whether any component replacement or service repair is required if the alert persists.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10253660: Index381, published March 26, 2024. https://static.nhtsa.gov/odi/tsbs/2024/MC-10253660-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253658: Index373, published March 26, 2024. https://static.nhtsa.gov/odi/tsbs/2024/MC-10253658-9999.pdf
  • NHTSA Manufacturer Communication PDF 10252957: developG, published February 13, 2024. https://static.nhtsa.gov/odi/tsbs/2024/MC-10252957-9999.pdf
  • NHTSA Manufacturer Communication PDF 10250483: ManualC, 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

Official NHTSA-hosted Tesla owner-documentation communications describe UMC_w014 as a wall plug adapter communication error that reduces charging current to 8A: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf

19. Frequently asked questions

What does Tesla alert UMC_w014 mean?

It means the Mobile Connector is unable to communicate with the wall plug adapter.

Why is charging slower with UMC_w014?

Tesla documentation states that, because the Mobile Connector cannot identify the wall-outlet type through the adapter, it automatically reduces charge current to 8A.

What should I do when UMC_w014 appears?

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

Does UMC_w014 mean service is required?

Not yet established by verified evidence.

20. Sources & verification

Verified
Show all 24 verified sources
Tesla UMC_w014: Wall plug adapter error - Charge rate reduced Plug… | EV Diagnostics