What was found
AFTER LANDING APU FAILED TO START AND APU FAULT LIGHT ILLUMINATED. GROUNDED - YES. PERFORMED APU BITE PROCEDURES, FOUND MAINT MSG 49-41011 "NO FLAME SHUTDOWN" LOGGED ON LEG 0, PERFORMED B737-9 IFIM TASK 49-40-00-810-804 STEP B(2)B, NO ACTIVE FAULTS NOTED. STARTED APU X3 LOADED IT, NO PROBLEM NOTED.