What was found
AFTER APU START, APU GENERATOR WILL NOT COME ON LINE/CONNECT TO BUSSES. APU SELECTOR SHOWS NO VOLTS OR FREQS. GROUNDED - YES. PERFORMED APU BITE REF B737-900 FIM 49-60 TASK 801. UNDER CURRENT STATUS MAINT MESSAGE 49-41252 START CONVERTER SHOWS VOLTAGE REGULATOR FAILED. REF FIM 49-40 TASK 813 REMOVED & REPLACED GENERATOR CONTROL UNIT AND START CONVERTER UNIT REF B737-900 AMM 24-21-81/401 AND AMM 49-41-61/401. REMOVED & REPLACED STARTER-GENERATOR WIRE HARNESS REF AMM 49-11-01/401. REMOVED & INSTALLED NEW W4722-0002-02 WIRE AND NEW SM5 PER B737-900 WDM 24-21-31. INSTALLED NEW TERMINAL PER B737 SWPM 20-30-11. ACCOMPLISHED OPS CHECKS FOR APU GCU IAW AMM 24-21-81 AND FOR SCU IAW AMM 49-41-61, OP CHECKS NORMAL. ORIGINAL SUBMISSION DATE: 11/30/2022