711C Help

I have about 10 hours on a 711C autopilot hooked to a TZ2. Up until know it has worked flawlessly. Last time out it just went off and would not turn back off. The TZ2 reported that it lost connection when it went off. I turned everything off and tried to restart with no luck. So other than connection to the TZ and the ground what else should I check before I pull it out and send it in? I had it installed but it's moored a long way from there. I read there is a fuse to check but the manual suggest having a professional check it. Suggestions?

What shutdown the pilot or the TZT2?
If the pilot, I would disconnect the pump wires and try without them. It could be the pump has shorted. Also ensure the proper termination plug is on the back of your pilot display head.