As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU DETECTOR INOPERATIVE. INSPECTED APU FIRE DETECTOR IAW 26-110-00, STEP H. FOUND TAIL PIPE DETECTOR WITH LOW RESISTANCE OF 37.70K OHMS. ACTUAL READING SHOULD BE 3945 OHMS. REMOVED AND INSTALLED TAIL PIPE DETECTOR M1925. OPS CHECKED 26-15-00-710-801. SYS CHECKED NORMAL.