!
error Velux
Error Code Yellow LED flashes on and off intermittently
Signifies interruption in the wiring for external detectors or break-glass points, or broken cables.
? What Causes This
Wiring issues with peripheral devices.
✓ How to Fix It
Check all wires from control unit to sensors; repair connections and resolve any faults.
Source: page 68 of the official manual
From the manual
This error code appears in:
Velux Kfx 210