Problem

The band/watch is supposed to use invisible light to measure the user's heart rate while they are sleeping at night, but the user can see a green light.

Cause

When measuring your heart rate, the band/watch automatically switches between visible and invisible light based on whether you are awake or asleep. The green light of the PPG sensor is mainly used when you are awake, and the invisible light is mainly used when you are asleep.

The indicator(s) will light up when you are asleep at night in the following scenarios:

• When Continuous heart rate monitoring is enabled, and the device detects that you are not asleep, the green indicator will light up.
• When Automatic SpO2 measurement is enabled, and the device is still, the red and green indicators will be steady on.

Solution

Generally, your band/watch switches to invisible light detection mode when it detects that you are asleep. If the indicator bothers you, try the following:

• Disable Continuous heart rate monitoring in the Huawei Health app.
• Disable Automatic SpO2 measurement if you have enabled it. Open the Huawei Health app, touch Devices and your device name to go to the details screen, then touch Health monitoring, and disable Automatic SpO2 measurement.