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Tesla CHG_u001

Charge rate reduced - Unexpected voltage drop Remove extension cords / Have wiring inspected

Common search variants: CHGu001 · CHG-u001 · CHG u001 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence. Verified evidence does establish that the vehicle has reduced charging speed in response to the detected voltage drop.
ServiceThe verified evidence directs inspection of building wiring; it does not establish when Tesla Service must be contacted.
Confidence95%

Quick answer

CHG_u001 means the vehicle reduced charging speed after its onboard charger detected a large voltage drop during charging. Tesla’s documented instruction is to remove extension cords and have the building wiring inspected.

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 CHG_u001 mean?

CHG_u001 means the vehicle reduced charging speed after its onboard charger detected a large voltage drop during charging. Tesla’s documented instruction is to remove extension cords and have the building wiring inspected.

2. Technical explanation

Verified Tesla owner-documentation evidence states that charging speed is reduced because the onboard charger detected a large voltage drop while charging. The alert specifically directs the owner to remove extension cords and have wiring inspected.

3. What system is affected?

AC charging supply path, including the building wiring and/or wall outlet, as evaluated during charging by the vehicle’s onboard charger.

4. How serious is this code?

Severity is not yet established by verified evidence.

5. Symptoms you may notice

  • Reduced charging speed.
  • CHG_u001 alert: “Charge rate reduced - Unexpected voltage drop Remove extension cords / Have wiring inspected.”

6. Possible causes

  • Problems with the building wiring and/or wall outlet.
  • An extension cord in the charging setup.

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 does establish that the vehicle has reduced charging speed in response to the detected voltage drop.

9. What you can safely do

  • Remove extension cords from the charging setup.
  • Have the building wiring inspected.
  • For Mobile Connector or Wall Connector status-light troubleshooting, refer to the applicable product Owner’s Manual at Tesla Charging & Adapter Product Guides.

10. Step-by-step troubleshooting

  1. Do not use an extension cord in the charging setup.
  2. Arrange inspection of the building wiring and wall outlet by an appropriate qualified professional.
  3. Refer to the applicable Tesla Mobile Connector or Wall Connector Owner’s Manual for status-light troubleshooting.

11. When to contact service

The verified evidence directs inspection of building wiring; it does not establish when Tesla Service must be contacted.

12. What the service center may check

  • Inspect the building wiring and/or wall outlet for the condition associated with the voltage drop.
  • Review Mobile Connector or Wall Connector status lights using the applicable product Owner’s Manual.

13. Possible repair or resolution

  • Remove an extension cord, if present.
  • Have the building wiring inspected. Further repair resolution is not yet established by verified evidence.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA manufacturer communication MC-10250483, published December 1, 2023, contains Tesla owner-documentation text for CHG_u001: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf
  • Additional NHTSA manufacturer communications listed in the verified evidence repeat this owner-documentation alert, including MC-10253660 and MC-10253658, published March 26, 2024.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla owner-documentation materials identify this alert for Tesla Model 3 (2017–2023), Model S (2012–2023), and Model X (2016–2023) in the US, according to the supplied applicability records. Source: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250483-9999.pdf

19. Frequently asked questions

What does CHG_u001 mean?

It means charging speed was reduced because the onboard charger detected a large voltage drop during charging.

Should I remove an extension cord?

Yes. The documented alert instruction says to remove extension cords.

What should be inspected?

Tesla’s documented guidance says to have the building wiring inspected. The evidence identifies building wiring and/or the wall outlet as likely causes.

Does this alert prove the vehicle needs repair?

No. That is not established by the verified evidence. The documented likely causes concern the building wiring, wall outlet, or an extension cord.

20. Sources & verification

Verified
Show all 24 verified sources
Tesla CHG_u001: Charge rate reduced - Unexpected voltage drop Remove… | EV Diagnostics