How do I perform a factory reset on the PetSafe Microchip Cat Flap?

Press and hold the button in the battery compartment for 15 seconds until the LED is activated, then the red LED will flash 5 quick times. The cat flap will return to Automatic Mode and be locked, and all programmed microchip IDs will be erased from memory. You will need to re-program all cats after performing a factory reset. (Page 7)