As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED TO PLATFORM AS A CONSEQUENCE OF APU DID NOT SUPPORT PNEUMATIC CHARGES FOR ENGINE STARTING. GPU WAS CONNECTED TO ENGINES STARTING AND APU WAS DEFERRED IAW MEL 49-1. DURING OVERNIGHT SERVICE APU WAS TESTED IAW MPCM 49-00-01 SETTING BOTH ENGINES IN 23 PERCENT OF N2 IAW MM 71-00-00, OPERATING CORRECTLY THE APU. DEFERRED REPORT WAS CLOSED.