The Samsung CLP-500 is a colour laser printer for home and office use. To save money you can refill your toner cartridges; however, doing so requires that you reset the toner cartridge, or you'll continue to receive an "Invalid Toner" error message that the toner will not work. You can reset the toner cartridge using a special Samsung CLP-500 toner reset fuse; you can purchase the fuse from online retailers. Resetting the toner cartridge requires some experience with electrical components and a soldering iron.
Remove the toner cartridge that you wish to reset. Locate the cartridge contacts assembly in the side of the cartridge. The assembly is approximately 1 inch long and has three copper contacts on the side.
Pry out the cartridge contacts assembly with a flathead screwdriver. The assembly has two fuses -- one connected to the two outside copper pins (Pin1 and Pin 3), and one connected to the middle pin and an outside pin (Pin 1 and Pin 2).
Secure the cartridge contacts assembly in a vice so that the fuses are facing upward. Do not overtighten the vice or you may damage the assembly.
Grasp the fuse connected to Pin 1 and Pin 3 with needle-nose pliers. Touch a hot soldering iron to the ends of the fuse to melt the solder so you can remove the fuse. Be careful not to touch the plastic on the assembly with the soldering iron. Try to melt the solder as close to the copper pins as possible.
Smooth out any remaining solder on the copper pins with the soldering iron, after you remove the fuse.
Hold the cartridge reset system fuse with needle-nose pliers. Touch one end to Pin 1 and solder it in place.
Touch the other end of the reset system fuse to Pin 3 and solder it in place.
Reinstall the cartridge contacts assembly into the toner cartridge. Reinstall the toner cartridge.
Print a test page to check that the toner cartridge is working properly.