As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB ACFT YAWED UNCOMMANDED. COMPLIED WITH QRH, DISCONNECTED YAW DAMPERS & YAWING PERSISTED. FD NR 2 WAS ENGAGED. ACFT RETURNED TO PHL, EMERGENCY DECLARED. LANDED AT 46,900 LBS, NORMAL LANDING. IAW WO 212612 WC 5 FOR TROUBLESHOOTING & WORK PERFORMED. R & R YAW DAMPER LINEAR ACTUATOR, OPERATIONS CHECKED GOOD.