What was found
FAULT LIGHT ILLUMINATED DURING 1ST APU START ATTEMPT AT FL 380. REATTEMPTED START AT FL 330 WAS SUCCESSFUL WITH NO FAULT LIGHT. ACFT GROUNDED. REPLACED APU INLET PRESSURE SENSOR IAW AMM 49-52-31 AND REPLACED APU INLET TEMPERATURE SENSOR IAW AMM 49-61-31. BOTH SENSORS LEAK CK GOOD. ACCOMPLISH APU BITE PROCEDURE IAW 49-60, TASK 801, NO FAULTS NOTED. ACCOMPLISH APU OPS CK IAW AMM 49-11-00. NO DEFECTS NOTED.