What was found
DURING APPROACH WHEN FLAPS WERE SELECTED FROM 9 DEG TO 22 DEG, EICAS MESSAGE (SPS ADVANCED). FLAP POSITION INDICATOR BOX WENT AMBER WITH AMBER DASH WITH NO FLAP INDICATION, RMU PAGE SHOWING NO FLAP INDICATION BUT AMBER DASHES, EICAS DID NOT PRESENT A FLAP FAIL MESSAGE, BUT WE PROCEEDED WITH FLAPS FAIL PROCEDURE AOM VOL 1, REPLACED FLAP POWER DRIVE UNIT. AC RETURNED TO SERVICE