What was found
APU FLUCTUATING . ACFT GROUNDED. ACCOMPLISHED APU BITE IAW FIM 49-60, TASK 801. NO CURRENT FAULTS. FAULT HISTORY SHOWS MESSAGE NR 49-11019, POWER INTERRUPT. INPUT MONITORING PARAMETERS: DELTA PRESS: 6.1 PSID, TOTAL PRESS: 21.0 PSIA, INLET PRESS: 14.5 PSIA, INLET TEMP: 5.1C, FUEL TMC: 119 MA. ACCOMPLISHED ALTERNATE DEACTIVATION REF CH5, TABLE 3, ITEM 1. ACCOMPLISHED MEGGER OF APU HARNESS CONNECTORS: P18, P19, P20, P21. NO FAULTS DETECTED. REF WDM 49-62-12, 49-52-31,49-71-21. DURING INSPECTION FOUND CONTAMINATION ON GROUND STRAPS: M83413-8-G016BB, M83413-8-G007BB. REQUIRES REPLACEMENT. REPLACED INLET TEMP SENSOR REF AMM 49-61-31. P21 CONNECTOR HAS CONTAMINATION AND REQUIRES REPLACEMENT. REPLACED P-21 CONNECTOR IAW CHAP 20 & WDM 49-71-21. ACCOMPLISHED APU OPS TEST IAW AMM 49-11-00-710-801 AND APU BITE PROCEDURE AMM 49-61-00-700-801, NO DEFECTS NOTED. VERIFIED EXTENSIVE CORROSION AT BONDING CABLES M83413-8-G016BB, M83413-8-G007BB, AND CONNECTOR P21. GROUNDING STRAPS ARE ADHERED TO PHENOLIC COMPRESSOR COVER. ALSO EXTENSIVE CORROSION ON MOST GROUNDING CABLES THROUGH OUT APU WIRING HARNESS. RECOMMEND APU REPLACEMENT. ON DEFERRAL.