TM 9-4120-385-14
Figure 4-37. Terminal Location, Heater
Thermostat (S3) (Overheat Safety).
Using a multimeter, check continuity between terminals 4 and 5,4 and 6.
3.
Connect multimeter to terminals 4 and 5. Using a heat gun, direct heat to
4.
sensing area and hold 3 to 4 inches away. Continuity should be broken within 5 to 6 minutes.
Switch may also be tested by placing a thermometer bulb on the sensing element
5.
and applying heat source. Continuity should be broken at 205 F 12 F (90 C 5 C) and
restored when switch cools to 139 F 4 F (61 C 9 C).
Connect multimeter to terminals 4 and 6 and repeat tests in step b above.
6.