Unable to Charge — Wall Connection Too Hot
The TESLA-CP_A102 (Tesla Charge Port (CP)) EV fault code means: Unable to Charge — Wall Connection Too Hot. This is a moderate severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- easy
- Estimated cost
- Electrician inspection/repair billed by the job — often a quick fix (re-torquing a loose connection). Not a vehicle repair.
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Common Symptoms
- Alert on the touchscreen: "Unable to charge - Wall connection too hot — Outlet or Wall Connector wiring must be checked"
- Charging at the Wall Connector stops
- Recurs at the same charging location
- Driving is unaffected
Probable Causes (Ranked by Likelihood)
- The building wiring connection to the Wall Connector is getting too warm, so charging stopped to protect the wiring — per Tesla, typically a building-wiring issue (often a loose connection), not the vehicle or the Wall Connector itself Likely
Frequently Asked Questions
What does CP_a102 mean on a Tesla?
Tesla's official meaning: the building connection to the Wall Connector is too warm, so charging stopped to protect the wiring and the Wall Connector. It's typically the building wiring — often a loose connection — not the vehicle or the Wall Connector.
What's the difference between CP_a101 and CP_a102?
Same underlying issue — heat at the building's wiring connection to the Wall Connector — different response. With CP_a101 the vehicle slows charging; with CP_a102 the connection got hot enough that charging stopped entirely.
How do I fix CP_a102?
Stop charging on that circuit and have an electrician inspect the building wiring connection to the Wall Connector — properly connected and torqued per the installation guide. Charge elsewhere until it's fixed.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
This is the harder-stop sibling of CP_a101: the connection got hot enough that the vehicle stopped charging entirely instead of just slowing down. Treat it as a wiring problem that needs fixing before you keep charging there.
Contact an electrician to inspect the building wiring connection to the Wall Connector — all wires properly connected and torqued per the Wall Connector installation guide (Tesla's official guidance).
A hot building connection under charging load is a classic loose-connection symptom and a fire risk if ignored — don't keep retrying on that circuit until it's inspected.
Charge elsewhere (another location or a Supercharger) until the wiring is fixed.
Sources 4
This page is built from documented references. Verify against your own service info before repair work.
- Tesla Model 3 Owner's ManualTroubleshooting Alerts (official Tesla alert text for CP_a102; verified against the official Model 3 manual PDF, software 2026.20)
- Tesla Model Y Owner's ManualTroubleshooting Alerts (confirms CP_a102 is documented across models)
- Tesla firmware alert reference (core-hacked/tesla-alerts-dictionary): cp_a102community-maintained dictionary, not an official manufacturer document
- Tessie Tesla alert statisticsthird-party Tesla alert reference with owner-telemetry frequency — not an official Tesla document
Commonly Affected Vehicles
- Tesla Model 3
- Tesla Model Y
- Tesla Model S
- Tesla Model X
- Tesla Cybertruck
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