What was found
GEAR HANDLE FOUND TO BE UNMOVABLE FOLLOWED BY A LANDING GEAR AIR/GROUND FAIL MESSAGE, RETURNED TO YYZ. MESSAGE EXTINGUISHED ON APPROACH. REMOVED AND REPLACED LANDING GEAR ELECTRONIC CONTROL UNIT, LANDING GEAR CONTROL LEVER AND AIR/GROUND POSITION RELAY IAW EMB AMMS 32-32-01, 32-32-02, AND 32-13-02. PERFORMED OPERATIONAL CHECKS IAW AMM 32-30-00 AND 32-52-00 WITH NO FURTHER DEFECTS NOTED. RETURNED AIRCRAFT TO SERVICE.