Disclaimer: Repairing electronic devices involves risk. Always ensure you have appropriate knowledge before attempting to troubleshoot powered circuits.

What is the printed on the front panel?

Blown protection fuse, open-circuit power transistor, or a dead op-amp.

The 10k or 5k linear pots on the front panel get dirty or crack. This causes the voltage to jump erratically.

Check the bridge rectifier diodes and the main switching MOSFET for shorts before replacing the fuse. 2. Bad Electrolytic Capacitors ("Bad Caps")

Look closely at the electrolytic capacitors on both the primary and secondary sides. Bulging tops or leaked electrolyte indicate high Equivalent Series Resistance (ESR). Replace them with high-temperature (105°C) equivalents.

: A "two seconds to black" symptom (where the screen flashes briefly then goes dark) often indicates a shorted secondary winding in the inverter transformers. Cold Solder Joints

Unplug the unit and discharge the main cap. Trace the circuit away from the positive leg of the main capacitor. Look for surface-mount or discrete through-hole resistors leading toward the VCCcap V sub cap C cap C end-sub

The Wannien 101V0 is a widely utilized power supply board found across a variety of consumer electronics, ranging from LED monitors and small televisions to budget-friendly audio equipment and networking devices. Because these boards are manufactured as cost-effective original equipment manufacturer (OEM) components, official documentation and free schematics can be incredibly difficult to source directly from the manufacturer.

The PSU is entering "hiccup mode" (over-current protection). Check secondary Schottky diodes for shorts. Degraded Electrolytic Capacitors

If you'd like more specific troubleshooting tips, you can tell me: on the board? What specific, non-functional symptoms are you seeing? I can then provide more detailed component testing steps. Wannien 101v0 Power Supply Schematic | PDF - Scribd