As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ENGINE START, APU AIR DROPPED TO 15 PSI, FLUCTUATING 2-3 PSI. MAX MOTORING ACHIEVED WAS 16% N2 ON RIGHT ENGINE.(<P>PERFORMED T/S PER FIM 36-10 FAULT TREE 840 AND BITE AIR SUPPLY MODULE PERFORMED AND FOUND NO FAULTS AT THIS TIME.</P>)