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Tesla UMC_w019

Mobile Connector to adapter connection hot Maximum charge rate reduced

Common search variants: UMCw019 · UMC-w019 · UMC w019 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence. Verified evidence confirms that the Mobile Connector has reduced charge current.
ServiceService need is not established by the supplied verified evidence.
Confidence95%

Quick answer

Tesla alert UMC_w019 means charging current was reduced because the Mobile Connector detected high temperature at the connection between its wall-plug adapter and 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_w019 mean?

Tesla alert UMC_w019 means charging current was reduced because the Mobile Connector detected high temperature at the connection between its wall-plug adapter and control box.

2. Technical explanation

This is a Mobile Connector charging alert, not a vehicle diagnostic trouble code. The verified manufacturer communication states that the Mobile Connector reduces charge current after detecting high temperature at the wall-plug-adapter-to-control-box connection.

3. What system is affected?

Tesla Mobile Connector and its wall plug adapter connection.

4. How serious is this code?

Severity is not established by the supplied verified evidence. The alert confirms that charge current has been reduced.

5. Symptoms you may notice

  • Maximum charge rate reduced.
  • A UMC_w019 alert is displayed.
  • The Mobile Connector has detected high temperature at the wall plug adapter and control box connection.

6. Possible causes

  • High temperature detected at the connection between the wall plug adapter and the Mobile Connector control box.
  • No further underlying cause is established by the supplied verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence. Verified evidence confirms that the Mobile Connector has reduced charge current.

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.
  • Tesla documentation identifies Tesla Supercharger and Destination Charging locations as alternative charging locations that can be found through the vehicle touchscreen map.

10. Step-by-step troubleshooting

  1. Confirm that the wall plug adapter is fully connected to the Mobile Connector control box.
  2. Refer to the Mobile Connector product owner's manual for status-light and charging-issue troubleshooting.
  3. No additional troubleshooting procedure is established by the supplied verified evidence.

11. When to contact service

Service need is not established by the supplied 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 10250483: ManualC, published December 1, 2023. https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253660: Index381, published March 26, 2024. https://static.nhtsa.gov/odi/tsbs/2024/MC-10253660-9999.pdf

16. Recall information

  • No recall is established by the supplied verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla manufacturer communications identify UMC_w019 as “Mobile Connector to adapter connection hot Maximum charge rate reduced.” Verified applicability: US Tesla Model 3 (2017–2023), Model S (2012–2023), and Model X (2016–2023).

19. Frequently asked questions

What does Tesla UMC_w019 mean?

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

What should I do for UMC_w019?

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

Does UMC_w019 confirm a failed part?

No. A failed part is not established by the supplied verified evidence.

20. Sources & verification

Verified
Show all 24 verified sources
Tesla UMC_w019: Mobile Connector to adapter connection hot Maximum… | EV Diagnostics