What was found
#2 ENG B LOOP FIRE DETECTION INOPERRATIVE. GROUNDED - YES. VERIFIED DISCREP. HARD FAIL. B737-900 FIM TASK 26-10 TASK 801. SHOWS A "WIRING OPEN/DETECTOR" FAULT. REF. FIM 26-10 TASK 805, RMVD M279 MODULE REF. MM 26-10-01, RMVD B LOOP WIRING FROM B DETECTORS. REF. B737-900 WDM 26-11/21, ALL DETECTORS OHM'D OUT GOOD. ENG. HARNESS WIRING RANG OUT POINT TO POINT - FOUND 2 MEG. OHMS BETWEEN LOWER FAN TERM TO LEFT CORE B TERM. (VIA THRU DP1601) SHAKE DOWN OF CORE WIRING HAD NO FLUX. DISCONNECTED DP1601 AND CLEANED SAME - RESIST. CHK'S NOW GOOD. M279 REINSTALLED REF. AMM 26-10-01, W/ AC RETURNED TO NML, #2 ENG. A&B OPS NML REF. AMM 26-10-00.