LG SPQP5BE-W Owner's Manual page 7

Checking the connection with the LED on the bottom of the wireless
subwoofer
You can check the connection status by looking at the LED on the bottom of the wireless subwoofer.
LED Color
Blinking green
Green
Red
Off
Status
Connecting in progress
Connected successfully
Bad connection, or the subwoofer is in standby
Power cable not connected
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