What was found
APU FAULT ON START. GROUNDED - YES. OBSERVING APU MDS DATA PAGE, APU ECU DOES NOT INITIALIZE WHEN EITHER APU SWITCH POSITIONED TO ON, OR WHEN MDS MAINT CTL APU SELECTED TO TEST. CYCLED APU ECU C/B, THEN NORMAL OPERATION RESTORED. ACCOMPLISHED APU OPERATIONAL TEST PER B737-9 AMM 49-11-00 WITH NO DEFECTS OBSERVED. NO MDS STATUS OR FAILURE MESSAGES PRESENT AT ANY TIME. ETOPS GROUND VERIFICATION SUCCESSFUL.