What was found
DURING THE MONTH OF JANUARY, SIX FUEL PRESSURE SWITCHES, P/N 100-389018-21 WERE REPLACED. THE TBR FOR THE SWITCHES WAS: 3,933.2 HRS FROM N NR 148SK; 1,418.2 HRS FROM N NR 831SK; 1,479.7 HRS FROM N NR 87SK; 2,525.6 HRS FROM N NR 881SK; 1,715.7 HRS FROM N NR 881SK; AND 1,780.4 HRS FROM N NR 91SK. THE AVERAGE TIME IN SERVICE OFR THESE SWITCHES WAS 2,142.1 HOURS. ALL OF THE FUEL PRESSURE SWITCHES WERE REMOVED DUE TO FLIGHT CREWS REPORTING AUXILIARY FUEL TRANSFER MALFUNCTIONS. REF: OPERATOR CONTROL NRS S2YA97007 AND 97ZZZX1797, 97ZZZX1798 AND 97ZZZX1800, 97ZZZX1801.