As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, LANDING GEAR RETRACT LEVER COULD NOT BE SELECTED UP. OVERRIDE WAS USED, NLG RETRACTED BUT MLG REMAINED DOWN. THE LT MLG TRAILING ARM HINGE PIN BOLT WAS BROKEN ALLOWING THE HINGE PIN TO ROTATE AND GIVE FALSE SIGNAL TO WOW SWITCHES. REPLACED BOLT.