As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI TO GATE APU FAULT LIGHT ILLUMINATED WHEN ATTEMPTING TO START APU. GROUNDED - YES. UPON ARRIVING, PERFORMED APU BITE CHECK REF B737-9 AMM 49-61-00. FOUND FAULT CODE 49-41181. PERFORMED B737-9 IFIM TASK 49-40-00-810-808 UP TO STEP C.4(A)(5). FAULT 49-41181 NOT ACTIVE. STARTED APU 3 TIMES WITH NO ISSUES.