Engine fire switch (P8) Switch positions L E F T Disch 1 2 L E F T 1 2 DISCH Switch locked Switch released electrically Switch pulled Switch released manually Electrical connector Push-pull contacts (internal) Engine fire override switch Solenoid energized Engine fire warning light Spring return (switch open) Rotary contacts (internal) Discharge 2 (switch closed) Spring return (switch open) Discharge 2 (switch closed) Center Engine fire override switch pushed and maintenance program for all types of continuous-loop  systems should include the following visual checks. These  procedures are examples and should not be used to replace  the applicable manufacturer’s instructions. Sensing elements of a continuous-loop system should be  inspected for the following: Figure 9-12.  Engine fire switches. Figure 9-13.  Engine fire switch operation. 1.  Cracked or broken sections caused by crushing or  squeezing between inspection plates, cowl panels, or  engine components. 2.  Abrasion caused by rubbing of the element on cowling,  accessories, or structural members. 3.  Pieces of safety wire or other metal particles that may  short the spot-detector terminals. 4.  Condition of rubber grommets in mounting clamps,  which may be softened from exposure to oils or  hardened from excessive heat. 5.  Dents and kinks in sensing element sections. Limits on  the element diameter, acceptable dents and kinks, and  degree of smoothness of tubing contour are specified  by the manufacturer. No attempt should be made to  straighten any acceptable dent or kink, since stresses  may be set up that could cause tubing failure. (See  illustration of kinked tubing in  Figure 9-14 .) 9-11