What was found
APU WILL NOT START. INTEREGATED CDU FAULT CODE 49-41248. STARTER CONVERTER UNIT SHOWS SYS INOPERATIVE. DURING BATTERY START WITH NO EXTERNAL POWER APPLIED, BATTERY STARTING VOLTAGE 25 VDC THEN DROPS TO A MINIMUM OF 19VDC WITH A MAX CURRENT DRAW OF -210 AMPS. MAX STARTING EGT 840 DEG C. AS STARTER CURRENT DROPS OFF AND APU SPOOLS UP FLIGHT DECK LIGHTS FLICKER AND CURRENT SURGES BETWEEN -54 TO -10 AMPS UNTIL STARTER CUTOUT. NO FAULTS LOGGED. TOTAL START TIME FROM START SWITCH ON TO APU GEN OFF LIGHT ON 1 MINUTE 30 SECONDS. APU STARTS IN 50 SECONDS WITH EXTERNAL POWER APPLIED AND NO CURRENT SURGES OR LIGHTS FLICKERING. R & R BATTERY REF T U CS 024147-000 PNC FOR PART CHANGE INFO. OPS CK APU WIHT NEW BATTERY OPS CK NML REF MM 49-11-00.