An awesome student from our education program made this wiki. It is not managed by iFixit staff.
Computer Won't Boot
Computer will not load past the start screen
First, check to ensure that the RAM is properly installed and inserted into the mother board; it is possible the RAM became loose. If the computer turns, nothing is displayed, and you hear the computer making a series of beeping noises, this may be a failure in the RAM. The RAM may also have a hardware failure if the computer constantly crashes when trying to load programs. See the RAM Replacement Guide.
Hard Drive Cable Loose or Faulty
During the computers start up, check that the boot options are to the correct hard drive by going to the options menu, as this may only be a software issue. If that has been ruled out, then this may be a problem in the hard drive or its connections. Ensure the hard drive is fully connected to the motherboard. Check the hard drive with another SATA cable (what is used to connect the hard drive to the motherboard) if this step proves fruitless. If it is connected with a function wire, and it still does not work, then the hard drive may have failed internally and will need to be replaced. See the Hard Drive Replacement Guide.
Computer Won't Turn On
Computer is unresponsive and will not turn on or charge
Check that the cables are plugged in, and that the battery is securely mounted in the computer. If the charging light is light on the cord, then the issue must be the battery and will most likely need replacement. See the Battery Replacement Guide.
Loose or Faulty Charging Cord
Ensure the the charging cord is fully inserted into both the outlet and the computer. For cords that have two cables, such as a power brick that a second cord connects to, ensure that cable is also plugged it. If the cord is indeed plugged in, the charging light does not come on and the computer is not charging, then the issue may be faulty wiring in the cord which may need replacing.
Keyboard Keys are Stuck or Unresponsive
Pressing the keys on the keyboard do not have any effect on the computer, or the keys are stuck in place
Keyboard Faulty or Unplugged
First, check that the keyboard is connected the motherboard via the ribbon cable attached to it; occasionally it can come undone while moving around. To replace the keyboard, see the Keyboard Replacement Guide.
Computer is Overheating and Turning Off On Its Own
The computer will turn off without any warning or go to a blue screen indicating an issue with the computer
Dusty Cooling Fan
If the HP is overheating to the point where it will shut itself off or you cannot hear the fans on, then it is most likely an issue with the fan. Try cleaning the dust out of the fans with a can on compressed air, as dust can cause the overheating and occasionally halt the movement of the fans. If the fan is not functioning after that, the fan or the connection to the motherboard may have become faulty, which would need replacement. See the Cooling Fan Replacement Guide.
Computer Won't Read Any Disks or Open Disk Tray
CD's make a strange noise in the drive and are not displayed on the computer screen, or does not spin at all
Defective Disk Drive
Check that there is nothing obstructing the disk drive both inside and out, to ensure it is not an outside problem. Make sure the disc is clean and readable to ensure it is not an optical reading device failure. For instructions on replacing the disk drive, see the Disk Drive Replacement Guide.