As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURN BACK DUE TO APU SHUTDOWN IN FLIGHT. LEFT GENERATOR ON MEL SO APU IS REQUIRED. APU RESTARTED ON 3RD ATTEMPT.(<P>PER ENGINEERING AND MANAGEMENT REQUEST, R/R APU HARNESS WIRE PN: W020-212R-24 IAW WDM 49-14-11-1 AND SWPM 20-25-00 AND SWPM 20-60-00. DUE TO APU BITE FLAG FOR OVERSPEED AFTER WIRE REPLACEMENT PERFORMED MULTIPLE STARTS OF APU W/ 1+ HOUR OF RUN TIME IN BETWEEN, NO SHUTDOWNS OF OVERSPEED FLAG. OPS CHECK GOOD.