As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THAT THE LANDING GEAR WOULD NOT RETRACT. ALSO HAD A LANDING GEAR AIR/GND FAIL ON EICAS. CAPT DIVERTED TO LGA. AIRCRAFT LANDED SAFELY WITH NO OTHER PROBLEMS. FOUND MAIN LEFT DOWNLOCK PROXIMITY SWITCH DEFECTIVE. REMOVED AND REPLACED LEFT MAIN PROX SWITCH IAW EMB140 AMM 32-61-02. ALSO, PERFORMED MULTIPLE GEAR SWINGS IAW EMB 140 AMM 32-30-00. OPERATIONAL CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.