What was found
APU APUC DETECTED FAULT THAT WOULD CAUSE AUTOMATIC SHUTDOWN OF APU IN UNATTENDED MODE OPERATION, OR COMPLETE LOSS OF APUC BUS ACTIVITY (BOTH L AND R 629) FOR 3 SECONDS AFTER THE APU MASTER CONTROL SWITCH HAS BEEN IN THE ON POSITION FOR TEN SECONDS. STATUS MSG-4910270 INACTV TA MODE. REPLACED APUC. AFTER APUC WAS INSTALLED, FAULT MSG, 49-12990 APPEARED - OIL FILTER ELEMENT CLOGGED. REPLACED OIL FILTER ELEMENT. ALL FAULTS CLEARED. APU OPS NORMAL.