As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EWR---CO3543, CREW REPORTED "AIR RETURN TO EWR: LANDING GEAR WOULD NOT RETRACT QRH UNSUCCESSFUL." MAINTENANCE REMOVED AND REPLACED LANDING GEAR CONTROL LEVER IAW EMB145 AMM #32-32-02. REMOVED AND REPLACED LGEU IAW EMB145 AMM #32-32-01. LANDING GEAR SWING OPERATIONAL CHECK GOOD. AIRCRAFT RELEASED FOR SERVICE.