LEDs

Three LEDs say what the device is doing: power, connection and bus activity. There are no patterns to decode; each one is on, off or blinking with the traffic.

LED	On the case	Meaning
Power	the power symbol	On while WiCAN runs. Off while it sleeps, and when it has no power. It also lights when the device is put into download mode for recovery over USB.
Connection	the WiFi symbol	On while someone is connected to WiCAN: an app on the TCP port, a phone over Bluetooth, the Monitor tab, or the MQTT broker. It says nothing about the WiFi link itself: a WiCAN joined to your network with nobody talking to it shows it off.
Data	the envelope	Blinks with the frames received from the CAN bus. Steady off means nothing is arriving: the ignition is off, the bit rate is wrong, or the bus is not connected.

Everything off
Asleep, or no power	WiCAN wakes when the battery voltage rises above the sleep voltage, see Sleep and battery alert. Plugged into a car with the ignition off, that is normal after the sleep delay.

On WiCAN OBD the three LEDs are on the face of the case under their symbols. On WiCAN USB the connection and data LEDs show next to the terminal labels.