Define PF1/PF2 key as Bluetooth switch by programming software (factory default is PF2 key).
Press and hold the PF2 key to hear a "tick" to turn on the Bluetooth function, while the Bluetooth icon appears and flashes on the display.
Press and hold the PF2 key, hear a "tick" to turn off the Bluetooth function.
Note: Bluetooth icon will stop flashing when connected; Bluetooth icon will flash when disconnected.
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Press and hold the on/off button for 5 seconds to enter pairing mode(Bluetooth pairing: red and blue alternating flash refining)