There are many possibilities when a MacBook cannot power on. Before handing it over to a technician for repair, you can try the following basic resets and possible solutions:

1. Check battery and charger issues: Make sure the charger is properly plugged in and connected to power. You can try testing the charger with another MacBook that uses the same type of charger.

2. Try restarting: Hold down the power button for a few seconds, and then press the power button again.

3. Reset SMC: System Management Controller (SMC) is responsible for managing many hardware functions of the MacBook, including power and thermal management. To reset the SMC, you can refer to official guide from Apple.

4. Reset NVRAM: NVRAM (non-volatile random-access memory) stores some system settings, including startup disk settings and display resolution. To reset the NVRAM, you can refer to official guide from Apple.

5. Check the startup disk: If your hard disk or solid-state drive has failed, your MacBook may keep trying to find a normal startup disk. You can press and hold the ‘Option’ key after pressing the power button to see if there is a normal startup disk.

6. Check the display: Inspect the LCD panel and backlight. You can check if the display emits backlight in a dark environment and shine a strong light, such as the flashlight function on a phone, to check for a faint image.

7. Further check the display: You can use ‘Clamshell mode’ to connect an external display. First, make sure the charger is properly plugged in and connected to power, then connect the external display, and then close the MacBook to force the output to the external display.

8. Disconnect external devices: Unplug all external devices, such as chargers, USB devices, Thunderbolt devices, etc., from the MacBook and try to boot up again.

If you have tried the above basic resets and possible solutions but your MacBook still cannot power on, you can bring your MacBook to our office located in Mong Kok for a free inspection. Our technicians will locate the problem and provide corresponding repair solutions.