TM 10-3930-659-20 Table 3-1.  Preventive Maintenance Checks and Services (PMCS) (Con't). Location Not Fully Item Item to Mission No. Interval Check/ Service Procedure Capable If: 8 Quarterly Gages and Visually inspect all gages, indica- Indicators tors, and warning lights for loose connections, proper operation, and other defects. 9 Semiannually Wiring and a.  Inspect wiring for defective insula Switches tion, breaks, and loose or corroded connections. b.  Check switches for proper opera- tion and defects. 10 Semiannually Fuel Filter WARNING Diesel fuel is combustible.  DO NOT smoke or allow open flame near fuel filter.  Failure to follow this warning will result In death or serious injury to personnel.  If you are burned, Immediately seek medical aid. ] Replace fuel filter (see para- graph 5-17). 11 Semiannually Engine Add corrosion inhibitor (Item 24, Ap- Radiator pendix C) to engine radiator through filler neck (see TM 750-254). 12 Semiannually Batteries WARNING Remove all Jewelry such as rings, dog tags, bracelets, etc.  If Jewelry contacts battery terminal, a direct short will result, causing Instant heating of Jewelry which will re- sult in severe Injury to personnel. 3-6