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Tesla CC_a004

Unable to charge - Wall Connector issue Wall Connector needs service

Common search variants: CCa004 · CC-a004 · CC a004 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeCharging may be unavailable from the affected Wall Connector. Whether charging is available through another charging source is not yet established by verified evidence.
ServiceIf CC_a004 persists after reconnecting and the specified circuit-breaker power cycle, consult an electrician or contact Tesla.
Confidence95%

Quick answer

Tesla alert CC_a004 means the Wall Connector detected an internal hardware issue and charging may be unavailable from that Wall Connector. Tesla’s published guidance is to reconnect; if the issue persists, power-cycle the Wall Connector at its circuit breaker for 10 seconds, then reconnect. If it continues, consult an electrician or contact Tesla.

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 CC_a004 mean?

Tesla alert CC_a004 means the Wall Connector detected an internal hardware issue and charging may be unavailable from that Wall Connector. Tesla’s published guidance is to reconnect; if the issue persists, power-cycle the Wall Connector at its circuit breaker for 10 seconds, then reconnect. If it continues, consult an electrician or contact Tesla.

2. Technical explanation

Verified Tesla material identifies CC_a004 as “Unable to charge - Wall Connector issue Wall Connector needs service.” The alert concerns Wall Connector hardware rather than establishing a fault in the vehicle. Tesla lists possible Wall Connector issues as: a contactor not working, failed self-test of the internal ground-fault monitoring circuit, a disconnected thermal sensor, or another hardware-component issue. These are possible issues, not a confirmed diagnosis for any individual installation.

3. What system is affected?

Tesla Wall Connector charging equipment / AC charging supply equipment.

4. How serious is this code?

Not yet established by verified evidence. The alert indicates a Wall Connector hardware issue that can prevent charging.

5. Symptoms you may notice

  • The vehicle displays CC_a004: “Unable to charge - Wall Connector issue Wall Connector needs service.”
  • Charging may be unavailable using the affected Wall Connector.

6. Possible causes

  • Wall Connector contactor not working.
  • Failed self-test of the Wall Connector’s internal ground-fault monitoring circuit.
  • Disconnected Wall Connector thermal sensor.
  • Another Wall Connector hardware-component issue.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Charging may be unavailable from the affected Wall Connector. Whether charging is available through another charging source is not yet established by verified evidence.

9. What you can safely do

  • Try reconnecting the Wall Connector to the vehicle.
  • If the issue persists, turn off the circuit breaker servicing the Wall Connector, wait 10 seconds, turn the breaker back on, and reconnect the Wall Connector to the vehicle.
  • If the issue remains, consult an electrician or contact Tesla.
  • See the installation guide for the Wall Connector.

10. Step-by-step troubleshooting

  1. Reconnect the Wall Connector to the vehicle.
  2. If CC_a004 persists, perform Tesla’s specified Wall Connector power cycle: turn off its servicing circuit breaker, wait 10 seconds, turn it on again, then reconnect.
  3. Do not attempt internal Wall Connector diagnosis or repair; Tesla’s verified guidance directs the owner to an electrician or Tesla if the condition persists.

11. When to contact service

If CC_a004 persists after reconnecting and the specified circuit-breaker power cycle, consult an electrician or contact Tesla.

12. What the service center may check

  • Determine why the Wall Connector reported an internal hardware issue.
  • Evaluate the listed possible conditions: contactor operation, internal ground-fault-monitoring self-test status, thermal-sensor connection, and other Wall Connector hardware components. Specific diagnostic procedures are not established by the verified evidence.

13. Possible repair or resolution

  • Not yet established by verified evidence. Tesla directs owners to consult an electrician or contact Tesla when the issue persists.

14. Affected vehicles

15. Related TSBs / service bulletins

  • NHTSA Manufacturer Communication PDF 10250480 (Tesla owner-manual material), published 2023-12-01: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250480-9999.pdf
  • NHTSA Manufacturer Communication PDF 10250484 (Tesla owner-manual material), published 2023-12-01: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • NHTSA Manufacturer Communication PDF 10250485 (Tesla owner-manual material), published 2023-12-01: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250485-9999.pdf
  • NHTSA Manufacturer Communication PDF 10253666 (Tesla owner-manual material), published 2024-03-27: 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_a004 and provide the owner action above. The supplied evidence applies in the US to Tesla Model 3, Model S, Model X, and Model Y across listed year ranges; overlapping records exist. Exact applicability for a specific vehicle and Wall Connector installation should be confirmed with Tesla. Last verified: 2026-09-23.

19. Frequently asked questions

What does Tesla CC_a004 mean?

It means “Unable to charge - Wall Connector issue Wall Connector needs service.” Tesla identifies it as a Wall Connector hardware issue.

What should I do first?

Reconnect the Wall Connector. If the alert persists, Tesla instructs turning off the circuit breaker servicing the Wall Connector for 10 seconds, turning it back on, and reconnecting.

What if CC_a004 returns after the power cycle?

Tesla directs you to consult an electrician or contact Tesla, and to refer to the Wall Connector installation guide.

Does CC_a004 prove that the vehicle is faulty?

No. The verified evidence identifies a Wall Connector hardware issue; it does not establish a vehicle fault.

20. Sources & verification

Accepted ResearchVerified
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Tesla CC_a004: Unable to charge - Wall Connector issue Wall Connector… | EV Diagnostics