I have a Dell Inspiron 3521 laptop. I can access the BIOS using F2 during boot. But inside BIOS I can't change any setting as the keyboard doesn't seem to type. The CPU fan seems to rotate fast inside BIOS. Tried to upgrade BIOS but it tells me to plug both AC adapter and battery and the laptop doesn't switch on with the battery plugged. I use it with direct current only. Please help.
I don't know if you tried this step yet but I like to suggest pressing the 'Power On' button for 15 seconds to release Static Flea Power by following steps below:
1. Power off system, removed all peripherals, AC adapter and then battery.
2. Press the 'Power On' button for 15 seconds. Replace the battery, adapter and then power on system. Hopefully computer starts normally.
If that step doesn't fix the problem, I suggest you run the diagnostic tool (F12 key) to check hardware on system. Please power on system, quickly start tapping the F12 key continuously. In the menu, stroll down to Diagnostic and click on it. Report back any error code.
If yes, I suggest you contact Technical Support for further assistance in the link below. Hopefully one of the Dell reps here on the forum, see the thread and be a help to you.
On some Dell computers, there's a Num Lock key on the keyboard. If there is one, you can press down on it to see if it will activate the keyboard again. If that doesn't work,try an external USB or Bluetooth keyboard to test if it responds correctly.