DIAGNOSIS ERR 02 is a specific DSP (Digital Signal Processor) communication error. The main board cannot talk to the audio processing chip.
FIX Perform a full power cycle. Unplug the soundbar from power. Also unplug your TV and any source devices. Wait 2 full minutes. Plug the soundbar in first, let it boot fully, then power on the TV. This clears the corrupted state.
IF THAT DIDN'T WORK A factory reset is required. Hold the 'Volume Down' and 'Source' buttons on the soundbar itself for 10 seconds until the display resets. You will need to re-pair the subwoofer and redo any custom settings.
HEADS UP If ERR 02 returns immediately after a factory reset, the DSP or main board has a hardware fault. Continued use is not advised as it can overheat.