What was found
REPORTED THE FOLLOWING DEFECT ON THE GROUND IN SFO. APU DID NOT START ON FIRST TWO ATTEMPTS. CHECKED APU OPERATION IAW AMM 491000, APU CHECKED OK. NO FURTHER ISSUES REPORTED ON SUBSEQUENT FLIGHTS. ACCORDING TO THE OPERATORS RECORDS, ALL AIRWORTHINESS DIRECTIVES, SERVICE BULLETINS, STC`S AND PMA`S ARE IN FULL COMPLIANCE WITH THE TYPE DESIGN CERTIFICATE AND ASSOCIATED REGULATORY REQUIREMENTS.