https://support.garmin.com/en-US/?partNumber=010-10997-09&tab=manuals
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Before you can pair the heart rate monitor with your device, you must put on the heart rate monitor.
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For most Garmin compatible devices, bring the device within 3 m of the heart rate monitor and use the device menu to pair manually. For some Garmin compatible devices, bring the device within 1 cm of the heart rate monitor to pair automatically.
TIP: Stay 10 m away from other ANT+ sensors while pairing.
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After you replace the heart rate monitor battery, you may need to pair it with the device again.
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