Unlock a stuck connector
OCPP functional block F — RemoteControl.
A station locks the cable into its socket while charging, so nobody can pull a live connector out. Occasionally it does not let go — the session ended badly, the driver's card failed at the end, or the mechanism jammed. The driver is standing next to a car they cannot detach.
This is the most support-call-generating operation in the whole protocol, and it is one request.
curl -X POST https://api.flowion.io/v1/connectors/$CONNECTOR/commands/unlock \
-H "Authorization: Bearer $TOKEN"
No body. The command is addressed to a connector, by its UUID.
The three answers#
| Status | Meaning |
|---|---|
unlocked | The cable is released |
unlock_failed | The station tried and could not |
not_supported | This connector has no lock to release |
not_supported is not an error. A station with a tethered cable — one
permanently attached — has nothing to unlock at the station end, and will say
so. If your fleet is mostly tethered DC hardware, this is the normal answer
and should not page anyone.
unlock_failed means the mechanism genuinely did not release. Usually
physical: something is binding the connector, or the actuator has failed. This
is a site visit.
Only when nothing is charging#
A station will refuse to unlock a connector with a live transaction, and it is right to. Unlocking mid-session would mean releasing a cable carrying current.
If a session is still running, stop it first — see Start and stop sessions remotely — then unlock. Expect the ordering to matter.
When a stuck cable is not stuck#
Before reaching for this, check whether the connector is actually locked or merely still occupied.
A connector in Finishing has ended its transaction but is not yet free —
typically because the cable is still plugged in at the vehicle. The
station may be waiting for the car to release its end, which no command of
yours can do.
Some stations are configured to unlock automatically when the cable is disconnected at the vehicle, and others deliberately hold the cable until the driver presents their card again. That is a station setting, and it changes what "stuck" means on your fleet. See Read and change charger settings.
So the order to check:
- Is a transaction still running? Stop it.
- Is the connector
Finishing? The cable may be held at the car's end. - Is the station configured to require a card to release? That is the intended behaviour, not a fault.
- Otherwise, unlock.
If the station is offline#
You get a 409, and there is nothing to be done remotely — the command
travels down a socket the station opened, and there is no socket. The driver
needs the station's own local release, or a site visit.
This is worth building into your support flow rather than discovering during an incident: a stuck cable on an offline station is a physical problem from the outset.