Thermostat backlight or display is very dim and hard to read, but device otherwise works.

Safety first: Turn OFF power at the breaker before removing the thermostat if you need to inspect it.

Steps to attempt:

• Adjust brightness: In the thermostat settings or Mysa app, increase display brightness if an option is available.
• Check ambient light sensor: If the model has an ambient light sensor, ensure it is not covered or blocked.
• Power cycle: Turn the breaker OFF for 2 minutes, then ON, and see if brightness improves.

If the display remains dim and unreadable, the backlight or driver has likely degraded. Replace the thermostat.