As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF ROLL FLIGHT CONTROL SYSTEM B LOW PRESSURE LIGHT ILLUMINATED CONTINUED TAKEOFF. RAN THE QRH AIRCRAFT WAS GROUNDED: CHECKLIST AND STANDBY RUDDER LIGHT AND YAW DAMPER LIGHT ILLUMINATED . FLIGHT ATTENDANTSREPORTED UNUSUAL HEAVY HUMMIMG NOISE FROM THE REAR OF AIRCRAFT.RETURNED TO ORD FOR LANDING. RETURNED TO FIELD LANDED OVERWIGHT WITHOUT INCIDENT. MAINTENANCE REPLACED SYSTEM B FLIGHT CONTROLS LOW PRESSURE SWITCH IAW AMM 27-09-61.