MK2 Temp sensor stopped working.

I've just noticed that the temperature reported by Hijack was -4C. I thought it may be something to do with the new beta (2.0b11) or Hijack v196 but I've installed both on my spare Rio and that reports correctly. So it looks like the temp sensor in my Empeg has died . If you're reading this Hugo can you give me details of the component and where I'll find it on the Mainboard so that I can replace it.

TIA