What was found
IN CLIMB RECEIVED A SKID INBD CAUTION MESSAGE FOLLOWED BY PARKING BRAKE SOV CAUTION MESSAGE. GEAR HANDLE WAS IN UP POSITION, BUT GEAR WAS STILL DOWN AND LOCKED WITH THREE GREENS. TRIED RECYCLING GEAR ONCE, BUT MESSAGES PERSISTED AND GEAR STAYED DOWN. RAN QRH FOR A SKID AND PARKING BRAKE SOV CAUTION MESSAGES, BUT MESSAGES PERSISTED. ABOUT 5 MINUTES AFTER INITIAL MESSAGES APPEARED WHEN ABOUT TO TURN BASE TO FINAL, GEAR CAME UP ON ITS OWN (HANDLE WAS STILL IN UP POSITION). ALL MESSAGES CLEARED THIS POINT WITH NO FURTHER ISSUES, BUT RETURNED TO FIELD. (FLT#4570) CLOSED / DEFERRED LANDING GEAR RETRACTION SYSTEM IAW MEL.