A wall switch doesn't turn its light on or off

Try these in order

1. Check that the POWER LED on the module is on. If it is off, the module has no power.
2. Check that phase is on P and neutral is on N, as marked on the module.
3. Check that each wall switch is wired between C and its own S terminal, with no loose or disconnected wires.
4. Never connect AC power to the wall switches or to C and S.

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• The module doesn't power on