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error Finder

Error Code ER3

Data connection was made but communication with the cloud resulted in failure due to corruption issues or extremely disturbed lines.

? What Causes This

Corrupted connection during cloud interaction, leading to data loss and disturbed signal propagation.

How to Fix It

Check WiFi strength and stability. Update firmware if available through Finder YOU app. Reinitialize WiFi settings on device.

Source: page 20 of the official manual

From the manual

Manual page 20 — Finder error ER3

This error code appears in:

Finder IB1C91 Bliss Wifi Chrono Thermostat