In this video, I repair a Levoit Core 300S air purifier that was sold as new but not turning on.
I bought the unit broken for 5€ and decided to diagnose the issue step by step.
The problem turned out to be a failed power supply IC, which caused the 5V rail to be missing.
Instead of fully rebuilding the power stage, I took a practical engineering approach and restored functionality by supplying 5V externally.
This video shows the disassembly, fault isolation, repair decision, and final test.
This is a real-world repair, not a production-grade fix — focused on learning, diagnosis, and getting a device working again.
If you enjoy electronics teardown, troubleshooting, and practical repairs, this one’s for you.
Disclaimer:
This repair involves working with mains voltage. Do not attempt unless you understand the risks and safety precautions.
