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Tesla UMC_a017

Charge rate reduced - Wall plug temperature high Wall outlet and wiring inspection recommended

Common search variants: UMCa017 · UMC-a017 · UMC a017 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeThe verified evidence states that charging is slowed, rather than stating that charging is unavailable. Whether continued charging is appropriate is not yet established by verified evidence.
ServiceAn inspection of the wall outlet and wiring is recommended. The supplied evidence does not specify a particular service provider or service appointment requirement.
Confidence95%

Quick answer

UMC_a017 means the Tesla Mobile Connector detected high temperature at the wall plug/outlet and reduced charging rate to protect the outlet. Tesla recommends inspection of the wall outlet and wiring.

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_a017 mean?

UMC_a017 means the Tesla Mobile Connector detected high temperature at the wall plug/outlet and reduced charging rate to protect the outlet. Tesla recommends inspection of the wall outlet and wiring.

2. Technical explanation

Verified Tesla owner-manual material filed with NHTSA states that this alert is triggered when the Mobile Connector detects that the outlet used for charging is becoming too warm. Charging is slowed as a protective response for the outlet. The same material states this is not typically an issue with the vehicle or the Mobile Connector.

3. What system is affected?

AC charging supply equipment: the wall outlet/plug connection and associated wiring used with the Tesla Mobile Connector.

4. How serious is this code?

The database severity is listed as unknown. Verified evidence does establish that the charging rate has been reduced because high wall-plug/outlet temperature was detected.

5. Symptoms you may notice

  • Tesla alert UMC_a017 is displayed.
  • Charging rate is reduced.
  • The Mobile Connector has detected high temperature at the outlet used for charging.

6. Possible causes

  • The wall outlet used for charging is becoming too warm.
  • Wall outlet and wiring inspection is recommended. Specific underlying electrical 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?

The verified evidence states that charging is slowed, rather than stating that charging is unavailable. Whether continued charging is appropriate is not yet established by verified evidence.

9. What you can safely do

  • Arrange inspection of the wall outlet and associated wiring, as recommended in the alert.
  • For Mobile Connector status-light and charging-issue information, refer to the applicable product owner’s manual.
  • Tesla owner-manual material identifies Tesla Supercharger or Destination Charging locations as charging alternatives that can be located using the vehicle touchscreen map.

10. Step-by-step troubleshooting

  1. The verified guidance is to have the wall outlet and wiring inspected.
  2. Refer to the product owner’s manual for troubleshooting Mobile Connector status lights and charging issues.
  3. No further user-performed diagnostic or electrical repair procedure is established by the supplied verified evidence.

11. When to contact service

An inspection of the wall outlet and wiring is recommended. The supplied evidence does not specify a particular service provider or service appointment requirement.

12. What the service center may check

  • Inspect the wall outlet and associated wiring, consistent with the alert recommendation.
  • No specific test procedure, measurements, or component-level service checks are established by the supplied verified evidence.

13. Possible repair or resolution

  • Resolution depends on the outcome of the recommended wall outlet and wiring inspection. A specific repair is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA manufacturer communications contain Tesla owner-manual information for UMC_a017, including NHTSA document 10250484 (published December 1, 2023): https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • Additional NHTSA-filed Tesla owner-manual communications in the supplied evidence repeat this alert guidance. No vehicle-specific repair TSB procedure is established by the supplied evidence.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official source: Tesla owner-manual content filed with NHTSA. Example: NHTSA Manufacturer Communication PDF 10250484, published December 1, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf. Supplied applicability records cover US Tesla Model 3 (2013–2024), Model S (2012–2024), Model X (2016–2024), and Model Y (2020–2024), with overlapping year ranges in the database.

19. Frequently asked questions

What does UMC_a017 mean?

It means the Mobile Connector detected high temperature at the wall plug/outlet, and charging was reduced to protect the outlet.

Is this usually a vehicle or Mobile Connector fault?

Tesla’s owner-manual material states that it is not typically an issue with the vehicle or the Mobile Connector.

What should be inspected?

The alert recommends inspection of the wall outlet and its wiring.

Can I still charge?

Verified evidence says charging is slowed. It does not establish whether continued charging is appropriate in every situation.

Can I drive the vehicle?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla UMC_a017: Charge rate reduced - Wall plug temperature high Wall… | EV Diagnostics