Charge Cable Blocked — Charge Port Latch May Be Frozen
The TESLA-CP_A078 (Tesla Charge Port (CP)) EV fault code means: Charge Cable Blocked — Charge Port Latch May Be Frozen. This is a minor severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- easy
- Estimated cost
- $0 — this is a cold-weather condition resolved by thawing; no repair is involved unless the latch fails in warm conditions too.
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Common Symptoms
- Alert on the touchscreen: "Cable blocked - Charge port latch may be frozen — Try using Defrost Car button in Mobile App"
- Charge cable cannot be removed from the charge port
- Appears in cold ambient temperatures
- Driving is unaffected once the cable is released
Probable Causes (Ranked by Likelihood)
- Ice on the charge port latch in cold weather is preventing it from unlatching the cable Likely
- Strain on the cable holding the latch under load Possible
Step-by-Step Diagnostic Procedure
First re-insert the charge cable fully to remove strain, then try unlatching again.
If it's still stuck, use the Defrost Car button in the Tesla mobile app for roughly 30-45 minutes. Tesla specifically notes the app's Defrost Car is more effective than adjusting climate controls on the touchscreen.
Turning on the rear defrost from the touchscreen can also help — some vehicles have a charge port inlet heater that activates with rear defrost in cold weather.
As a last resort, use the charge port manual release cable in the trunk (left side, sometimes recessed behind trim): make sure charging is stopped, open the trunk, pull the release cable downward, and remove the charge cable.
Frequently Asked Questions
What does CP_a078 mean on a Tesla?
Tesla's official meaning: the charge port latch can't release the charge cable and the vehicle detects cold ambient temperature — the latch may be frozen. It's a cold-weather condition, not a hardware fault.
How do I get a frozen charge cable out of my Tesla?
Re-insert the cable fully to remove strain and try again. Then run Defrost Car from the Tesla app for 30-45 minutes (Tesla says this works better than the in-car climate controls). Rear defrost can also help on vehicles with a charge port inlet heater. If all else fails, pull the manual release cable on the left side of the trunk with charging stopped.
How do I prevent CP_a078 in winter?
Preconditioning the vehicle before unplugging helps thaw the charge port area, and Tesla's cold-weather guidance covers additional practices. The alert itself causes no damage — it's the latch protection working while frozen.
Sources
This page is built from documented references. Verify against your own service info before repair work.
- Tesla Model 3 Owner's Manual — Troubleshooting Alerts (official Tesla alert text for CP_a078)
- Tesla Model Y Owner's Manual — Troubleshooting Alerts (confirms CP_a078 is documented across models)
- Tesla firmware alert reference (core-hacked/tesla-alerts-dictionary): cp_a078
- Tessie Tesla alert statistics