It might be better if you log on to the Thetford website and navigate to spare parts for your C2.
You will find they have exploded diagrams showing all the parts- including the fuse carrier. You should then be able to work out how to get to it and the wiring.
Geoff somewhere in Wales
December 2010
Automatic Answer
While you wait for answers, we may have found some information which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix toilets.