PS2 is on, but no signal
The tray has become misalligned. If you want to fix it on your own heres what you do. Remove the 6 (or 8 depending on generation) screws on the bottom. Remove the warranty sticker on the back by the power switch. With the front towards you, lift the top while tilting slightly toward the front and pivoting it by the power/eject buttons. Either remove the button assembly by popping it off the lid or just be careful not to tear the cable. Remove 4 philips screws from the cd mech lid and lift off. Remove two philips screws from the tray hinge. Lift and slide tray out of front. Push white gear frame at front of tray area to the right and hold it there while you put the tray back in. Reassembly is reverse of disassembly.