TM-9-2350-311-20-2 Maintenance Manual Volume 2 for M109 Cab Download
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TM 9–2350–311–20–2 3–129 j. NBC SYSTEM CIRCUIT — CONTINUED (3) NBC CONTROL BOX ASSEMBLY INDICATOR LIGHT ILLUMINATES, BUT M2A2 AIR PURI- FIER DOES NOT OPERATE. INITIAL SETUP Applicable Configuration M109A4/M109A5 howitzers Test Equipment Multimeter (item 6, Appx H) Tools Artillery and turret mechanic’s tool kit (SC 5180–95–CL–A12) Equipment Condition Vehicle MASTER switch to OFF (TM 9–2350–311–10) CAB NBC POWER switch to OFF (TM 9–2350–311–10) 1. Disconnect wire 135 from M2A2 air purifier. 2. Turn MASTER and CAB NBC POWER switches to ON. 3. Place red multimeter lead in wire 135 and black lead to ground. 4. Check for voltage. Is battery voltage present? Replace M2A2 air puri- fier (para 17–3). 1. Place one multimeter lead on one end of NBC ground lead that connects to M2A2 air purifier and other lead on NBC ground lead that connects to M27 periscope. 2. Check for continuity. Is continuity present? A yes no Repair NBC ground lead (para 8–10). B yes no CONTINUED ON NEXT PAGE M2A2 AIR PURIFIER – + GROUND LEAD WIRE 135 – +