First thoughts are:
1) Check Fastlane (Link on top of page) for thier cost.
2) If you are handy with a multimeter, I suspect someone in the Diesel forum will tell you how to check the unit.
3) IF the unit is fried, the fault codes should indicate so. Not sure, but your multimeter with duty cycle might provide the answer. Again, the diesel forum will help.
4) Do a search on your model and engine control. Results might prove interesting.
5) Try car-parts.com for a used unit.