EPCOS NTC 1.0 Thermistor. -- Circuit Board failure is often due to the "sacrificial" destruction of the thermistor used to protect the circuit from high voltage and high current surges that could occur after a lighting strike during thunderstorms or other power surge. Normally the thermistor protects the circuit on start-up, providing a relatively high resistance (1 Ohm) at ambient temperature to limit "InRush Current", and then essentially disappearing from the circuit (0.04 ohm) when the current is near or equal the design current of 9 Amp. The part will fail when a power surge is much greater than the power handling capability of the part. The correct replacement thermistor is: EPCOS B57237S109M. ICL (Inrush Current Limiters) are a cost-effective way of limiting the inrush of current that can damage other components in a switching power supply and other devices when the equipment is turned on..