Is something wrong with my Tesla?

Probably not. Tesla’s own documentation says this alert usually reflects the external equipment, and the everyday causes (a station waiting for payment or running on a schedule) have nothing to do with your car. The test that settles it costs nothing: charge somewhere else. One successful session at another station or a Supercharger is acquittal.

Why does my own home charger show CP_a066?

Check its scheduling first. Many home chargers (and the car itself) have off-peak charging timers, and a unit set to start at midnight will sit “not ready” all evening by design. Also check any load-sharing setup if two EVs share a circuit. If no schedule explains it, power-cycle the charger at the breaker (off, ten seconds, on), and re-plug.

Every station I try shows this alert. Now what?

That pattern is the one that earns a service visit: when AC charging fails everywhere while Supercharging still works, the suspicion shifts to your car’s charge port communication electronics. Book service in the app and describe the everywhere-pattern explicitly. Until it’s fixed, Superchargers and DC fast charging generally remain your reliable option.

Can I do anything to force the session to start?

No, and that’s by design. The station is the gatekeeper here, and the car won’t draw power until the station’s signal allows it. Your levers are the legitimate ones: complete the station’s activation, adjust its schedule, re-seat the cable, or move to other equipment. Anything beyond that belongs to the station operator or, in the rare car-side case, Tesla Service.

CP_A066 Tesla: Charging Equipment Not Ready: See Equipment Instructions to Start Charging

Low

Quick answer

CP_a066 means the charging station itself is telling your Tesla “not yet”: the equipment isn’t ready or hasn’t authorized the session. Nine times out of ten it’s the station waiting for a payment, an app activation, or its own scheduled-charging timer. Your car is usually fine; the fix is on the station’s screen, not in your Tesla.

What it means

When you plug into any AC charging station, the station and the car negotiate over a communication line before any power flows. CP_a066 means that negotiation reached a polite refusal: the station is connected and talking, but its signal says charging isn’t allowed to start yet. Tesla’s manual is unusually direct about whose problem this typically is: the alert “does not typically indicate an issue with your vehicle.”

The two scripted reasons are mundane. First, the station may be deliberately delaying: many home chargers and some public units have scheduled charging or load-management features that hold the session until off-peak hours. Second, the station may want authorization before it serves you: a tap of an RFID card, an app activation, a credit card at the terminal. Until that handshake completes, the station tells every car the same thing: not ready.

The one case worth real attention is when the alert follows your car from station to station, brand to brand. That pattern inverts the odds and suggests the car’s side of the communication (the charge port’s pilot-signal circuitry) needs a look, which is a service visit, not a driveway repair.

CP_A066 symptoms: what you'll notice

The touchscreen shows “Charging equipment not ready; See equipment instructions to start charging” and no charge begins
The cable is seated and latched, the port light is on, but the session never starts, often at a public AC station or someone else’s home charger
The same car charges normally at a Supercharger or at a different station, which is the giveaway that the equipment, not the car, was the holdout

Common causes

Ordered from most to least likely.

1.

The station requires activation or payment first

The most common story at public AC chargers: the unit wants an RFID card, a network app session, or a credit card before it will authorize. The car reports the station’s “not authorized” signal as this alert.
2.

The station’s scheduled charging or load management is delaying

Home chargers and workplace units frequently hold sessions for off-peak windows or to share a circuit among several cars. The session starts later by design: the alert just narrates the wait.
3.

A station fault or stale session

Charging stations are computers in the weather; they hang. A unit that needs a power-cycle, or that never properly closed its last session, can refuse everyone until it’s reset by the operator.
4.

Rarely: the vehicle’s charge-port communication

If every station everywhere shows this alert, the car’s side of the pilot-signal conversation is suspect. That’s charge port electronics: a Tesla Service diagnosis, with Supercharging usually still available in the meantime.

How to fix it: diagnosis, step by step

Cheapest and most likely checks first.

1 Read the station, not the car

Look at the charging unit for instructions: a screen prompting payment, an LED pattern, a sticker explaining its app or card activation, a posted schedule. Complete whatever activation it wants and watch whether the session starts. At a home unit, check its app for scheduled-charging settings that are politely making you wait.
2 Try a different stall, then a different station

Move the cable to the next stall or unit. If charging starts, the first unit was the problem: report it to the operator. If you can, also try a different brand of station or a Supercharger; a car that charges fine elsewhere has just proven its own hardware innocent.
3 Re-seat the cable and restart the handshake

Unplug, wait a few seconds, and plug back in firmly: the negotiation runs fresh each time the cable seats. At a home charger you can also power-cycle the unit at its breaker (off, ten seconds, on) to clear a hung session before trying again.
4 If the alert follows the car everywhere, book service

A CP_a066 at one or two stations is the equipment’s fault. The same alert at every AC station you touch (while Supercharging still works) points at the charge port’s communication circuitry. Schedule service in the app and say exactly that pattern out loud; it shortcuts the diagnosis.

Parts & tools you may need

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Related codes

Frequently asked questions

What does code CP_A066 mean?: CP_a066 means the charging station itself is telling your Tesla “not yet”: the equipment isn’t ready or hasn’t authorized the session. Severity is low: plan the repair, but it isn’t an emergency.
Is something wrong with my Tesla?: Probably not. Tesla’s own documentation says this alert usually reflects the external equipment, and the everyday causes (a station waiting for payment or running on a schedule) have nothing to do with your car. The test that settles it costs nothing: charge somewhere else. One successful session at another station or a Supercharger is acquittal.
Why does my own home charger show CP_a066?: Check its scheduling first. Many home chargers (and the car itself) have off-peak charging timers, and a unit set to start at midnight will sit “not ready” all evening by design. Also check any load-sharing setup if two EVs share a circuit. If no schedule explains it, power-cycle the charger at the breaker (off, ten seconds, on), and re-plug.
Every station I try shows this alert. Now what?: That pattern is the one that earns a service visit: when AC charging fails everywhere while Supercharging still works, the suspicion shifts to your car’s charge port communication electronics. Book service in the app and describe the everywhere-pattern explicitly. Until it’s fixed, Superchargers and DC fast charging generally remain your reliable option.
Can I do anything to force the session to start?: No, and that’s by design. The station is the gatekeeper here, and the car won’t draw power until the station’s signal allows it. Your levers are the legitimate ones: complete the station’s activation, adjust its schedule, re-seat the cable, or move to other equipment. Anything beyond that belongs to the station operator or, in the rare car-side case, Tesla Service.