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Tesla UMC_w005

Unable to charge with Mobile Connector Voltage too low / Try a different wall outlet

Common search variants: UMCw005 · UMC-w005 · UMC w005 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging with the Mobile Connector may be unavailable or interrupted while this alert is present. The verified documentation directs the user to try a different wall outlet.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

UMC_w005 means the Tesla Mobile Connector cannot charge, or charging was interrupted, because it detected insufficient wall-outlet supply voltage or an unexpected voltage drop. Try a different wall outlet.

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_w005 mean?

UMC_w005 means the Tesla Mobile Connector cannot charge, or charging was interrupted, because it detected insufficient wall-outlet supply voltage or an unexpected voltage drop. Try a different wall outlet.

2. Technical explanation

Verified Tesla owner-documentation evidence submitted to NHTSA states that UMC_w005 occurs when the Mobile Connector either does not detect enough supply voltage from the wall outlet or detects an unexpected drop in that voltage. The alert applies to charging with the Mobile Connector.

3. What system is affected?

Tesla Mobile Connector and the wall-outlet power supply used for charging.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • The vehicle cannot charge.
  • Charging is interrupted.
  • The vehicle displays UMC_w005: “Unable to charge with Mobile Connector Voltage too low / Try a different wall outlet.”

6. Possible causes

  • The Mobile Connector does not detect enough supply voltage from the wall outlet.
  • The Mobile Connector detects an unexpected drop in supply voltage from the wall outlet.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Charging with the Mobile Connector may be unavailable or interrupted while this alert is present. The verified documentation directs the user to try a different wall outlet.

9. What you can safely do

  • Try a different wall outlet.
  • 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 charging alternatives; these can be located using the vehicle touchscreen map.

10. Step-by-step troubleshooting

  1. Try a different wall outlet.
  2. Refer to the Mobile Connector owner’s manual for troubleshooting of its status lights and charging issues.

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 (published December 1, 2023) contains Tesla owner-documentation content for UMC_w005: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253660 (published March 26, 2024) contains Tesla owner-documentation content for UMC_w005: 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 documentation: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf. Verified applicability is US-market Tesla Model 3 (2017–2023), Model S (2012–2023), and Model X (2016–2023), based on the supplied applicability records.

19. Frequently asked questions

What does Tesla alert UMC_w005 mean?

It means the vehicle cannot charge, or charging is interrupted, because the Mobile Connector does not detect enough supply voltage from the wall outlet or detects an unexpected supply-voltage drop.

What should I do when UMC_w005 appears?

Try a different wall outlet. Tesla documentation also directs users to the product owner’s manual for Mobile Connector status-light and charging troubleshooting.

Can I use another charging location?

Tesla documentation identifies Tesla Supercharger and Destination Charging locations as charging alternatives that can be found on the vehicle touchscreen map.

Does this alert prove that the vehicle needs service?

Not yet established by verified evidence.

20. Sources & verification

Verified
Show all 24 verified sources
Tesla UMC_w005: Unable to charge with Mobile Connector Voltage too low… | EV Diagnostics