2) Installing the cartridge Open the printer�s front cover and flip up the cartridge lock lever. Insert the cartridge into the carriage and push down the cartridge lock lever to lock the cartridge in place. When the front cover is closed, the carriage moves to the capping position. When installing the scanner cartridge, all the LEDs are lit at 75% power output at the home position for a max. of 100 sec., and preheated to stabilize the LED output. The computer will display a message saying "Warming up scanner cartridge. Please wait." will appear. After the message appears, all the LEDs are lit at 50% power output for a max. of 600 sec. to retain the temperature.