E09 displayed and thermostat touchscreen or buttons do not respond correctly

Safety: Turn off power to the HVAC system before removing the thermostat front housing.

• Step 1 – Clean the screen:
  • Use a soft, dry microfiber cloth to gently clean the touchscreen.
  • Remove any screen protectors or covers that might interfere with touch.
• Step 2 – Reboot and reset:
  • Power cycle the thermostat at the breaker.
  • If E09 persists, perform a factory reset using the Gosund app if local touch is unresponsive.
• Step 3 – Check ribbon cable (advanced):
  • With power off, carefully separate the front panel from the wall plate.
  • Inspect the flex ribbon cable connecting the touch panel to the main PCB.
  • Ensure it is fully seated in its connector and not torn.
• Step 4 – Replace front panel or thermostat:
  • If the glass is cracked or the ribbon is damaged, the front touch assembly must be replaced.
  • On many Gosund models, the touch panel is integrated with the main unit; replace the entire thermostat if parts are not available separately.