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Tesla CP_a078

Cable blocked - Charge port latch may be frozen Try using Defrost Car button in Mobile App

Common search variants: CPa078 · CP-a078 · CP a078 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceNot yet established by verified evidence.
Confidence95%

Quick answer

Tesla alert CP_a078 means the charge-port latch cannot unlatch the connected charge cable while cold ambient temperature is detected. Tesla’s documented action is to fully reinsert the cable to remove strain, try unlatching again, and use the Defrost Car button in the Tesla mobile app if needed.

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 CP_a078 mean?

Tesla alert CP_a078 means the charge-port latch cannot unlatch the connected charge cable while cold ambient temperature is detected. Tesla’s documented action is to fully reinsert the cable to remove strain, try unlatching again, and use the Defrost Car button in the Tesla mobile app if needed.

2. Technical explanation

Verified Tesla owner-manual communications filed with NHTSA describe CP_a078 as a cable-blocked alert. The alert is associated with a charge-port latch that cannot release the charge cable when cold ambient temperature is detected; the latch may be frozen. This evidence establishes a cold-weather cable-release condition, not a general charging-system or high-voltage-battery fault.

3. What system is affected?

Charge port latch / charge-cable release function.

4. How serious is this code?

Unknown. The supplied verified evidence does not assign a severity level.

5. Symptoms you may notice

  • CP_a078 alert is displayed.
  • The charge cable cannot be unlatched from the charge port.
  • Cold ambient temperature is detected.

6. Possible causes

  • Cold ambient temperature is detected and the charge-port latch may be frozen.
  • Not yet established by verified evidence: other causes of this alert.

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.

9. What you can safely do

  • Reinsert the charge cable fully into the charge-port inlet to remove strain on the cable.
  • Try again to unlatch the charge cable.
  • Use the Defrost Car button in the Tesla mobile app, as stated in the alert title.

10. Step-by-step troubleshooting

  1. Fully reinsert the charge cable into the charge-port inlet.
  2. Attempt to unlatch the cable again.
  3. Use Defrost Car in the Tesla mobile app if needed.
  4. Not yet established by verified evidence: further owner troubleshooting steps.

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

  • Official NHTSA manufacturer communications/owner-manual publications document CP_a078 and its cold-weather cable-release guidance. Example: NHTSA MC-10250484-9999, published December 1, 2023: https://static.nhtsa.gov/odi/tsbs/2023/MC-10250484-9999.pdf
  • The supplied evidence does not establish a repair TSB, repair procedure, or component replacement for CP_a078.

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official source: Tesla owner-manual content filed with NHTSA. It states that the charge-port latch cannot unlatch the charge cable when cold ambient temperature is detected and directs the user to reinsert the cable fully to remove strain, retry unlatching, and use Defrost Car in the mobile app. The evidence applies in the US to supplied Tesla applicability entries: Model 3 (2013–2024 across overlapping records), Model S (2012–2024 across overlapping records), Model X (2016–2024 across overlapping records), and Model Y (2020–2024 across overlapping records).

19. Frequently asked questions

What does Tesla CP_a078 mean?

It means the charge-port latch cannot unlatch the charge cable and cold ambient temperature is detected; the alert indicates the latch may be frozen.

What should I do when CP_a078 appears?

Fully reinsert the cable into the charge-port inlet to remove strain, then try to unlatch it again. The alert also directs use of Defrost Car in the Tesla mobile app.

Is CP_a078 a battery fault?

Not yet established by verified evidence. The supplied official material specifically describes a charge-port latch/cable-release condition in cold ambient temperature.

Does CP_a078 require service?

Not yet established by verified evidence.

20. Sources & verification

Accepted ResearchVerified
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Tesla CP_a078: Cable blocked - Charge port latch may be frozen Try… | EV Diagnostics