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Tesla CC_a028

Unable to charge - Incorrect switch setting Wall Connector rotary switch must be adjusted

Common search variants: CCa028 · CC-a028 · CC a028 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNo at the affected Wall Connector while CC_a028 is present; the alert states that charging is unavailable. Charging capability after correction or with other equipment is not yet established by verified evidence.
ServiceContact Wall Connector service if the alert persists after an electrician has adjusted the internal rotary switch to a valid operating-current setting and power has been restored.
Confidence95%

Quick answer

Tesla alert CC_a028 means charging is unavailable because the Wall Connector has an incorrect internal rotary-switch setting. Tesla’s published guidance is to have an electrician set it to a valid operating-current setting; if the issue remains afterward, the Wall Connector requires service.

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1. What does CC_a028 mean?

Tesla alert CC_a028 means charging is unavailable because the Wall Connector has an incorrect internal rotary-switch setting. Tesla’s published guidance is to have an electrician set it to a valid operating-current setting; if the issue remains afterward, the Wall Connector requires service.

2. Technical explanation

CC_a028 is a Tesla OEM charging alert: “Unable to charge - Incorrect switch setting Wall Connector rotary switch must be adjusted.” The verified manufacturer communication states that the rotary-switch setting is incorrect. The specified correction is adjustment of the Wall Connector’s internal rotary switch to a valid operating-current setting, using the applicable Wall Connector Installation Manual. This is an issue identified at the Wall Connector, rather than a verified vehicle-system fault.

3. What system is affected?

Tesla Wall Connector charging equipment; specifically, its internal rotary switch and operating-current configuration.

4. How serious is this code?

Unknown. The supplied verified evidence does establish that charging is unavailable, but does not assign a severity level.

5. Symptoms you may notice

  • Unable to charge.
  • Tesla displays CC_a028: “Unable to charge - Incorrect switch setting Wall Connector rotary switch must be adjusted.”

6. Possible causes

  • Incorrect Wall Connector internal rotary-switch setting.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

No at the affected Wall Connector while CC_a028 is present; the alert states that charging is unavailable. Charging capability after correction or with other equipment is not yet established by verified evidence.

9. What you can safely do

  • Have a qualified electrician adjust the Wall Connector’s internal rotary switch to a valid operating-current setting in accordance with the applicable Wall Connector Installation Manual.
  • Do not attempt internal Wall Connector work yourself.
  • After the electrician has completed the work and restored power, reconnect the Wall Connector to the vehicle and try charging again.
  • If the issue persists, arrange Wall Connector service.

10. Step-by-step troubleshooting

  1. Confirm that the displayed alert is CC_a028.
  2. Refer the electrician to the applicable Wall Connector Installation Manual for the correct rotary-switch/current-setting correlation.
  3. Following professional adjustment and restoration of power, reconnect the Wall Connector and retry charging.
  4. If CC_a028 continues, the verified guidance states that the Wall Connector requires service.

11. When to contact service

Contact Wall Connector service if the alert persists after an electrician has adjusted the internal rotary switch to a valid operating-current setting and power has been restored.

12. What the service center may check

  • Verify the Wall Connector internal rotary switch is set to a valid operating-current setting according to the applicable Wall Connector Installation Manual.
  • After the setting correction and power restoration, verify whether charging resumes when the connector is reconnected to the vehicle.
  • If charging remains unavailable, service the Wall Connector.

13. Possible repair or resolution

  • Professional adjustment of the Wall Connector’s internal rotary switch to a valid operating-current setting.
  • Wall Connector service if the issue persists after the setting is corrected.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10250484, published December 1, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253666, published March 27, 2024: https://static.nhtsa.gov/odi/tsbs/2024/MC-10253666-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified NHTSA-hosted Tesla manufacturer communications describe CC_a028 as an incorrect Wall Connector rotary-switch setting. They direct use of the Wall Connector Installation Manual, professional adjustment to a valid operating-current setting, a charge retry after power restoration, and Wall Connector service if the condition persists.

19. Frequently asked questions

What does Tesla code CC_a028 mean?

It means charging is unavailable because the Wall Connector has an incorrect rotary-switch setting.

Can I adjust the Wall Connector rotary switch myself?

The verified guidance directs owners to have an electrician adjust the internal rotary switch. Do not perform internal Wall Connector work yourself.

What should happen after the setting is corrected?

After the electrician completes the work and restores power, reconnect the Wall Connector to the vehicle and try charging again.

What if CC_a028 remains after adjustment?

The verified guidance states that the Wall Connector requires service.

Is it safe to drive with CC_a028?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla CC_a028: Unable to charge - Incorrect switch setting Wall… | EV Diagnostics