What was found
MAST MOMENT INDICATION UNRELIABLE DURING START RUN-UP. UNABLE TO REDUCE BELOW 8% WHEN CENTERED, ALSO JUMPED AROUND WHEN CYCLIC WAS NOT BEING MOVED. DURING TROUBLESHOOTING OF MAST MOMENT SYS, UPEAK, UPEAK1, AND UPEAK2 VOLTAGES WERE OUT OF TOLERANCE. SUBBED IN SPU FOR TROUBLESHOOTING AND VOLTAGES CORRECTED. REPLACED SPU IAW AMM 63-42-00, 4-1; MOC OK.