Unplug the connector on the motherboard and check the lighting condition of the power supply.

• If the power supply lights up, then troubleshoot according to "Mainboard causing the power supply voltage to drop."
• If the power supply still does not light up, it is necessary to measure the input and output voltages of the power supply. The normal input voltage is AC220-240V, and the output voltage is DC24V.

1. If there is no input voltage, but only this power supply is not lighting up, it indicates that there is a loose connection or break in the circuit.
2. If the input voltage is normal, but there is no output voltage, the power supply needs to be replaced.