As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON GEAR RETRACTION THE CREW RECEIVED A L/G AIR/GND FAIL MESSAGE ON THE EICAS. FOLLOWED SHORTLY BY E1-2 REVERSE DISAGREE MESSAGE. THE CREW RETURNED TO THE FIELD AND BOTH MESSAGES CLEARED ON GEAR EXTENSION. A NORMAL LANDING WAS MADE. UPON INSPECTION BY MAINTENANCE, IT WAS FOUND THAT THE NOSE LANDING GEAR WAS NOT EXTENDING OR CENTERING PROPERLY. THE NOSE STRUT WAS SERVICED AND A LOOSE CONNECTOR ON THE RT AFT DOWN LOCK SENSOR WAS RE-SECURED. ALL OPERATIONAL CHECKS WERE GOOD.