Have you checked all the fuses in your ski? I had the same problem last week with my 2000 GTX and when I checked the fuses (in my case located in the MPEM, in the forward hull beneath the front storage bin) I found one blown. Changed the fuse and everything went back to normal.
There are also additional fuses in the electrical box in the aft hull, near your battery. Might as well check all of those too.
Grant Boshoff
May 2009