The engine stop solenoid on my new DS4510HS failed a few hours after delivery. Started fine about twenty times that day, then failed completely.
I identified the problem by finding the stop solenoid 10 amp fuse had blown and kept blowing when I replaced it. The solenoid itself got hot.
The dealer delivered and replaced it within 12 hours and said that this was not an uncommon problem in new machines but once replaced, then they did not find that customers had further problems.
I guess that sitting all that time on the delivery blocks and in containers contribute to the problem.
Anyway after 130 hours (or 4 months) it has started first time every time .
My tractor was made in 2010 so I am not sure if they now have an upgraded solenoid or not but the replacement one looked exactly the same.
Not one other thing has gone wrong with the tractor so I am pretty happy.
If it fails completely and you want to get it back to the shed, you can easily remove the solenoid (and seal the housing with a small rag or something to stop the diesel splashing out) and the tractor will start.
To stop it just push your finger into the housing against a rod and that will turn the engine off.