As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE LANDING GEAR WOULD NOT RETRACT AFTER TAKEOFF FROM EWR. THE AIRCRAFT WAS RETURNED TO EWR WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND GROUND SPOILER INTERLOCK VALVE YOKE WORN. THE INTERLOCK VALVE WAS REMOVED AND REPLACED IAW MM 27-62-61, PAGE 403. IN ADDITION, THE LANDING GEAR SAFETY SENSORS WERE ADJUSTED AND TESTED IAW MM 32-09-01. THE GEAR WAS CYCLED SEVERAL TIMES AND OPERATIONAL CHECKS WERE GOOD.