As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU OIL LEVEL BITE CHECK IS UNKNOWN, MAINT MESSAGE 49-94304. OIL LEVEL SENSOR CIRCUIT FAILURE. ACFT GROUNDED. REMOVED AND REPLACED THE APU OIL LEVEL SENSOR IAW AMM 49-94-11-000-801, AND AMM 49-94-11-400-801, RAN APU FOR 5 MINUTES TWICE FOR OIL LEAKS, NO LEAKS NOTED. CHECKED FMC-CDU FOR RECENT FAULTS, NO FAULTS FOUND ON BOTH STARTS.