My ps4 doesn't turn on and has a solid blue light. What can I do?

Since you have tried unplugging the device lets try other options. If possible, try replacing the power cable with one from a any other PS4 or PS3 and see if the issue persists when turning the console on. Just to make it sure that your power cable is ok.

See if the hard drive is seated properly and isn't damaged to fix the blue light of death

1. Turn off your PS4 completely by holding the power button for at least 7 seconds
2. Once the power indicator has completely shut off, remove the power cable, then all the other cables from your PS4
3. Slide off the hard disk drive bay cover and check if the internal hard drive is seated properly
4. If possible, unscrew the one screw that is holding the hard drive in place and re-seat it back into its slot.
5. Once you've checked or reseated the drive, put the hard drive bay cover back on, plug all the cables back in and see if the problem persists when turning the console on
6. If possible, check whether the hard drive itself works by setting it into another PS4 and turning it on.
   

Please try this and get back with status….