As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED AFTER PUTTING THE GEAR SELECTOR IN THE UP POSITION. THE GEAR FAILED TO RETRACT, 3-4 MINUTES LATER THE PILOT REPORTED THE GEAR CAME UP ON ITS OWN. PILOT THEN PUT THE GEAR IN THE DOWN POSITION AND RETURNED TO BASE. PROBABLE CAUSE AT THIS TIME UNKNOWN. INSTALLED NEW AND IMPROVED RELAY IAW DATE CODE. (K)