As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LANDING GEAR HANDLE WOULD NOT ALLOW LANDING GEAR TO RETRACT. RECEIVED LG AIR/GND FAIL MESSAGE AND RETURNED TO DFW. REMOVED AND REPLACED PROXIMITY SWITCH IAW EMB AMM 32-63-02 AFTER FINDING PIN A SHORTED. OPERATIONAL CHECK GOOD, RETURNED AIRCRAFT TO SERVICE.