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Troubleshooting Condensation Under the Screen of a Water Resistant Device
Garmin® devices can experience temporary condensation, moisture, or fogging inside of the lens when you transition to an environment with a significantly different temperature. To decrease the chances of this occurring, make the transition in temperature as gradual as possible. If condensation does occur, move to a warmer environment to promote evaporation.
If condensation, moisture, or fogging does not go away after a period of time in a warmer environment it is possible the seals that provide water resistance have failed. This can also be said if there are dried water spots on the inside of the glass or visible puddles of water inside the device.
If you are using a screen protector on your watch ensure the condensation isn't simply between the screen protector and watch face.
Being mindful of these signs of water ingress and natural condensation will help determine if a repair/replacement is needed. For more information on water ingress please visit Garmin's water rating website.