As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 5936, CLE TO BDL. AFTER TAKEOFF THE FLIGHT CREW RECEIVED A LANDING GEAR AIR/GROUND FAIL MESSAGE ON EICAS AND THE LANDING GEAR WOULD NOT RETRACT. THE FLIGHT RETURNED TO CLE AND LANDED WITHOUT INCIDENT. MAINTENANCE REPORTED CMC MESSAGES OF LGEU FAIL AND NOSE WOW PROX SWITCH FAILURE. IT WAS THEN FOUND THAT THE NOSE LANDING GEAR PROX SWITCH WAS NOT GETTING POWER AND WHEN A NEW HARNESS WAS SLAVED IN THE SYSTEM OPERATED NORMALLY. THE HARNESS WAS THEN REPLACED AND THE SYSTEM OPS CHECKED GOOD.