As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED AFTER REPEATED ACTUATIONS OF FIRE DETECTION WARNING TEST SWITCH, SWITCH BUTTON DETACHED FROM SWITCH BODY CAUSING SWITCH TO SHORT AND ACTIVATE WARNING HORN. PILOT DECLARED AN EMERGENCY AND DIVERTED TO BUR AIRPORT WITHOUT INCIDENT. (X)