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Tesla UMC_a016

Mobile Connector control box temperature high Maximum charge rate reduced

Common search variants: UMCa016 · UMC-a016 · UMC a016 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging can occur at a temporarily reduced current according to the alert description. Whether charging should continue in a particular situation is not yet established by verified evidence.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

Tesla alert UMC_a016 means the Mobile Connector detected increased temperature inside its control-box housing and temporarily reduced charge current.

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_a016 mean?

Tesla alert UMC_a016 means the Mobile Connector detected increased temperature inside its control-box housing and temporarily reduced charge current.

2. Technical explanation

This is a Mobile Connector charging alert, not a verified diagnosis of a vehicle fault. The documented effect is a temporary reduction of charging current after the Mobile Connector detects increased temperature inside its control-box housing.

3. What system is affected?

Tesla Mobile Connector control box / mobile charging equipment.

4. How serious is this code?

The supplied evidence does not assign a severity level. Charging performance is affected because the maximum charge rate is reduced.

5. Symptoms you may notice

  • UMC_a016 alert displayed.
  • Maximum charge rate reduced.
  • Charge current temporarily reduced.

6. Possible causes

  • Increased temperature detected inside the Mobile Connector control-box housing.
  • The Mobile Connector being covered by something or a nearby heat source are conditions specifically identified for the owner to check. Any further 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 can occur at a temporarily reduced current according to the alert description. Whether charging should continue in a particular situation is not yet established by verified evidence.

9. What you can safely do

  • Make sure the Mobile Connector is not covered by anything.
  • Make sure there is no heat source nearby.
  • Refer to the Mobile Connector product owner's manual for troubleshooting of Mobile Connector status lights and charging issues.

10. Step-by-step troubleshooting

  1. Confirm that the alert is UMC_a016.
  2. Check that nothing is covering the Mobile Connector control box.
  3. Check for a nearby heat source.
  4. Use the Mobile Connector owner's manual for further status-light and charging-issue 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 10250484, published December 1, 2023, documents UMC_a016 in Tesla owner-manual material: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • Additional supplied NHTSA manufacturer communications reproduce the same owner-manual alert information. No vehicle-specific repair procedure is established by the supplied evidence.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla owner-manual material states that charge current is temporarily reduced because the Mobile Connector detected increased temperature inside its control-box housing. It instructs owners to ensure the Mobile Connector is not covered and that no heat source is nearby. The verified applicability records are US Tesla Model 3 (2013–2024), Model S (2012–2024), Model X (2016–2024), and Model Y (2020–2024), with overlapping year records in the supplied database. Source: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf

19. Frequently asked questions

What does Tesla UMC_a016 mean?

It means the Mobile Connector detected increased temperature inside its control-box housing, so charge current has been temporarily reduced.

Why is my charging rate lower?

The verified alert description says the maximum charge rate is reduced because the Mobile Connector detected increased internal control-box temperature.

What should I do for UMC_a016?

Make sure the Mobile Connector is not covered by anything and that there is no heat source nearby. For further troubleshooting, refer to the Mobile Connector product owner's manual.

Does UMC_a016 require service?

Not yet established by verified evidence.

Can I drive with UMC_a016?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla UMC_a016: Mobile Connector control box temperature high Maximum… | EV Diagnostics