I don't think that's a model that exists. The PK5500 and PK5501 are keypad models.
There isn't a whole lot of data stored in the keypad itself are you sure you need to reset the keypad and not the control panel?
Resetting the keypad itself would clear things like zone labels, chime options, etc.
There are several keypad resets available:
Code:
* 8 [installer code] 995 * Resets keypad options to factory default
* 8 [installer code] 996 * clear zone labels
* 8 [installer code] 999 * Resets keypad EEPROM to factory default (may effectively reset everything, not certain)