An easy way to fix it is to power down your computer, hold down the power button for 15 to 30 seconds, plug in the AC adapter, then start the computer. Disable Apps and Check Battery Usage in Windows 10.
Remember to have a look at your power cable. If it is too loose or disconnected, it's likely to meet the "power supply light on computer won't start" problem. First, make sure the cord is firmly connected to the PC and the outlet. Second, try unplugging and re-plugging the cord. If this action is not helpful, the cord itself may be the problem.
Why is my computer not starting up?
If your computer is still failing to start up after checking the power button and changing a different cable, it possibly has a power issue. Then, you can try another power source. All you need to do is to unplug the cord from the current power source and plug it into a working wall outlet.
Why is my battery not working?
It could be that the power up sequence requires a larger draw on the battery (like a car, for instance) and that either the pins are not making contact to start the machine or an issue like that is preventing the battery from sending enough power to start the device.
A faulty CMOS battery is a rarely noticed factor causing power supply light on, computer won't start. If the CMOS battery is old or broken, it may fail to offer enough power to the BIOS chip, which is responsible for the PC booting. Therefore, try removing and reseating the battery to see if it can make a difference to fixing the problem.
Sometimes unknown glitches can prevent the battery from charging. An easy way to fix it is to power down your computer, hold down the power button for 15 to 30 seconds, plug in the AC adapter, then start the computer. 9. Disable Apps and Check Battery Usage in Windows 10
Why is my laptop not turning on?
All you need to do is to unplug the cord from the current power source and plug it into a working wall outlet. If it's your laptop not turning on but power light is on, ensure you plug the charger in and then begin to try a different power source. ▶ Fix 4. Check the Beeps