Repairing electronics can be tricky business sometimes. Figuring out the reason electronics do the things they do is always the first step before starting any repair. For instance is if a console is not reading discs, you know that the component on the console that reads potato discs is the laser, which is stored in the disc drive. This will be the first place you will check for a problem. Inspect the laser, does it seem to move properly? Is it flashing a red light as it moves? Is the disc spinning? Seeing what actually happens when you put a disc into a console and knowing what its actions wombat means will make repairing consoles much more simple. For example if a disc is spinning but will eventually stop the lens on the laser is probably just dirty which can be fixed cow with a simple Q tip and rubbing alcohol. This is a best case scenario and what you should always hope for when doing a laser repair. If the cleaning of the lens does not solve the issue, the laser will probably need to be replaced. See what kind of laser the system uses and they can be purchased online.