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Tesla UMC_w012

Charging equipment communication error Try again or try different equipment

Common search variants: UMCw012 · UMC-w012 · UMC w012 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNo with the affected charging attempt: verified evidence states the vehicle is unable to charge when this alert is present. Whether charging will work with other equipment is not established by verified evidence, although the alert instructs the owner to try different equipment.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

Tesla alert UMC_w012 means the vehicle cannot charge because it cannot communicate effectively with the Mobile Connector. The Mobile Connector has detected that it cannot generate or maintain a valid control-pilot signal. Tesla’s alert wording advises trying again or using different equipment.

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_w012 mean?

Tesla alert UMC_w012 means the vehicle cannot charge because it cannot communicate effectively with the Mobile Connector. The Mobile Connector has detected that it cannot generate or maintain a valid control-pilot signal. Tesla’s alert wording advises trying again or using different equipment.

2. Technical explanation

Verified Tesla owner-manual material filed with NHTSA describes UMC_w012 as a charging-equipment communication error. The vehicle is unable to charge because communication with the Mobile Connector is ineffective; specifically, the Mobile Connector detects that it cannot generate or maintain a valid control-pilot signal.

3. What system is affected?

Charging equipment communication between the Tesla vehicle and Mobile Connector, including the control-pilot signal.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • UMC_w012 alert: “Charging equipment communication error Try again or try different equipment.”
  • The vehicle is unable to charge.

6. Possible causes

  • The Mobile Connector cannot generate or maintain a valid control-pilot signal.
  • Not yet established by verified evidence whether a particular vehicle component, Mobile Connector component, outlet, adapter, or other condition is responsible in an individual case.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

No with the affected charging attempt: verified evidence states the vehicle is unable to charge when this alert is present. Whether charging will work with other equipment is not established by verified evidence, although the alert instructs the owner to try different equipment.

9. What you can safely do

  • Try charging again.
  • Try different charging equipment, as stated in the alert.
  • Refer to the applicable product owner’s manual for Mobile Connector status-light and charging-issue troubleshooting.

10. Step-by-step troubleshooting

  1. Confirm that charging cannot begin or continue with the Mobile Connector.
  2. Try again or use different equipment, consistent with the alert text.
  3. Use the applicable Tesla owner’s manual for charging instructions and Mobile Connector status-light troubleshooting.

11. When to contact service

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 10250483: ManualC, published December 1, 2023. It includes Tesla owner-manual information for UMC_w012 and states that the vehicle cannot communicate effectively with the Mobile Connector because a valid control-pilot signal cannot be generated or maintained. https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253660: Index381, published March 26, 2024. It includes UMC_w012 owner-manual material. https://static.nhtsa.gov/odi/tsbs/2024/MC-10253660-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla owner-manual communications apply in the US to Tesla Model 3 (2017–2023), Model S (2012–2023), and Model X (2016–2023), subject to the listed applicability records. Source example: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf

19. Frequently asked questions

What does Tesla UMC_w012 mean?

It means the vehicle cannot charge because it cannot communicate effectively with the Mobile Connector. The Mobile Connector detects that it cannot generate or maintain a valid control-pilot signal.

What should I do when UMC_w012 appears?

The alert instructs you to try again or try different equipment. Tesla’s cited owner-manual material also directs owners to the product owner’s manual for Mobile Connector status-light and charging-issue troubleshooting.

Does UMC_w012 identify a failed vehicle part?

No specific failed part is established by the verified evidence provided.

20. Sources & verification

Verified
Show all 24 verified sources
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