Do I need to replace the NTC in the heater of my Bosch WTL5500?

My Bosch WTL5500 has stopped working. The internal computer is obviously functioning because the count down time and all lights are normal, however no sound comes from the relays and the machine remains non-moving and cold. Inside the heater is a small black component marked "NTC" - I think this is the temperature sensor. My meter tells me that this component appears to be open circuit. I believe at cold there should be some reasonably low resistance. I could prove that this is the problem by bridging the sensor wires - is this sensible? Also, even if I have located the problem, what is the chance of being able to purchase this component or a complete heater? I am in the UK so a general "no chance" or "keep searching" will do !!!!