For battery-powered devices...
For battery-powered devices (such as wireless wall switches, RF remote controls, and battery-operated sensors), first check whether the battery is depleted.
Even in the case of freshly purchased devices, it may happen that the factory-installed battery is too weak, or it may have already been discharged while sitting in storage, and therefore needs to be replaced.
With battery-powered wireless switches, a typical sign of battery depletion is when the indicator LED lights up when you touch the button, but the switch is no longer able to send the RF signal. So, if you notice that the LED lights up when operating a battery-powered RF switch or remote control, it could still mean the battery is on its way out.
Replace the battery, and if that doesn’t solve the issue, read on.
For devices powered by mains electricity...
First, make sure the device is connected to a power source with a correct voltage. Consult the product manual for the required voltage. Some devices run on the standard 230V AC mains voltage, while others require 5V or 7V–32V AC or DC input.
You can find the required input voltage and power specifications on the technical datasheet available in the device’s webshop listing, as well as in the user manual.
Also check whether the device is connected with the correct polarity: make sure phase and neutral (L / N for AC devices) or positive and negative (+/- for DC devices) are not reversed.
If you are using devices powered by 5V / 12V / 24V DC adapters, make sure the power supply is working properly, the correct voltage is measured at the output, and that the power supply can provide the minimum current required by the smart device.
Is it a smart device that works with only a phase wire and no neutral?
Most 230V AC smart electrical devices require both a live (phase) and a neutral wire to function, but there are special types that operate with a single-live-wire, so without a neutral wire.
However, even in such cases, it's essential that the circuit can close properly — these devices will only work if a load (such as a lamp or other appliance) is connected. If you have a relay or switch that only uses a live wire, make sure to connect a lamp or another load to the switched output, as the switch won’t work at all with only a phase wire and no load.
In most cases, a small capacitor module, also called as an “anti-flicker module,” is also needed. This should be installed at the light/lamp between the live and neutral wires. Check that this module is properly connected, as its absence or a poor connection may cause live-only devices fail to function.
Check for loose connections
Make sure the device is properly wired. A common cause of issues is improper conductor connection at the device’s terminals, leading to contact failure. Double-check that the wires are securely connected!
If the device is powered on, you should be able to turn it on and off using the physical ON/OFF switch—regardless of if it has been paired or not (assuming the device has a physical button; some multi-channel relays don’t).
In the case of smart relays or smart sockets, you may also hear a clicking sound during switching, and the status LED on the device should light up after turning on.
If you’re certain the device is powered, but no LEDs light up and it cannot be operated by any button, it’s likely that the device is faulty and needs to be replaced.