go to www.thetford-europe.com
or
www.thetford.com.au for those in Australia.
on page 3 is 'Ask thetford' you can send them eamil using their online form.
carry out through servcing and you come to free pdf downloads just select your toilet before you get there. Could be fuse blown don't know where it is on that model. Do a test by turning on a 12volt light you can see and press flush see if light dims if it does then I would say pump is jammed when you take it out turn it upside down see if you can access the impelar and turn it slowly with small screwdriver or similar until it feel fairly free try it that sometimes works.
Failing that replace pump when you are sure that the current is reaching the pump.
Bob
March 2010