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Tesla UMC_w013

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

Common search variants: UMCw013 · UMC-w013 · UMC w013 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging is indicated as reduced to 8A by the verified evidence. Whether charging can continue in every 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_w013 means the Mobile Connector cannot communicate with its wall plug adapter. Charging current is automatically reduced to 8A because adapter temperature cannot be monitored. Tesla’s instruction is to fully plug the adapter into the Mobile Connector and retry.

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1. What does UMC_w013 mean?

Tesla alert UMC_w013 means the Mobile Connector cannot communicate with its wall plug adapter. Charging current is automatically reduced to 8A because adapter temperature cannot be monitored. Tesla’s instruction is to fully plug the adapter into the Mobile Connector and retry.

2. Technical explanation

This is an OEM charging alert for the Tesla Mobile Connector and wall plug adapter connection. Verified owner-documentation evidence states that the Mobile Connector is unable to communicate with the wall plug adapter. As a result, the Mobile Connector reduces charge current to 8A because it cannot monitor the adapter temperature.

3. What system is affected?

Tesla Mobile Connector and its wall plug adapter.

4. How serious is this code?

Severity is not specified in the verified diagnostic record. The verified evidence confirms reduced charging current to 8A.

5. Symptoms you may notice

  • The vehicle displays UMC_w013: “Wall plug adapter error - Charge rate reduced.”
  • Mobile Connector charging current is automatically reduced to 8A.

6. Possible causes

  • The Mobile Connector is unable to communicate with the wall plug adapter.
  • A more specific underlying cause 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?

Charging is indicated as reduced to 8A by the verified evidence. Whether charging can continue in every situation is not yet established by verified evidence.

9. What you can safely do

  • Follow Tesla’s stated instruction: fully plug the wall plug adapter into the Mobile Connector and retry.
  • For Mobile Connector status-light or charging troubleshooting, refer to the applicable Tesla owner documentation.

10. Step-by-step troubleshooting

  1. Unplug the wall plug adapter from the Mobile Connector, fully reconnect it, and retry charging, consistent with Tesla’s alert instruction.
  2. If the alert remains, further troubleshooting steps are not yet established by the supplied verified evidence.

11. When to contact service

Whether Tesla Service is required is not yet established by verified evidence.

12. What the service center may check

  • Confirm whether the Mobile Connector can communicate with the wall plug adapter. No further service checks are established by the supplied evidence.

13. Possible repair or resolution

  • Fully seating the wall plug adapter in the Mobile Connector and retrying is the only resolution instruction established by the verified evidence.
  • Any repair or replacement requirement is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10253660, published March 26, 2024: https://static.nhtsa.gov/odi/tsbs/2024/MC-10253660-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253658, published March 26, 2024: https://static.nhtsa.gov/odi/tsbs/2024/MC-10253658-9999.pdf
  • NHTSA Manufacturer Communication PDF 10250483, published December 1, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf
  • NHTSA Manufacturer Communication PDF 10238120, published May 22, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10238120-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla owner-documentation communications apply this alert to US Tesla Model 3 (2017–2023), Model S (2012–2023), and Model X (2016–2023).

19. Frequently asked questions

What does Tesla UMC_w013 mean?

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

Why is charging reduced with UMC_w013?

Tesla states that charge current is automatically reduced to 8A because the Mobile Connector cannot monitor the wall plug adapter temperature.

What should I do for UMC_w013?

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

Does UMC_w013 require service?

Not yet established by verified evidence.

20. Sources & verification

Verified
Show all 24 verified sources
Tesla UMC_w013: Wall plug adapter error - Charge rate reduced Plug… | EV Diagnostics