Hey Paul, here is some info from another forum. Note that in the middle is a link to Spektrum where they address an issue with the units and possible solution. They also state that if that does not fix it the unit can be sent in for a software update. Looks like it could be several things but perhaps it can be figured out via process of elimination. PS, I crapped out my Mach .15 stock motor on my xxx-nt. I have an OS 12 cvr coming in soon. With a little luck I'll be at the track NEXT Saturday.
Ron
I had the same kind of problem.
There were two possible causes. One was the potential for the current draw of my servos to cause enough of a voltage drop or spike that the
Spektrum receiver would shut down on me. Same deal, Would go to failsafe and then wouldn't respond again until you switched it off and back on. This can happen if your battery is litterally too small and can't supply enough current. If the wires used are too small etc. You see where i'm going with this.
The other situation thing i changed that may have fixed is is the routing of the coax antenna cable in the Spektrum module. Mine was one of the ones routed past the power circuits and caused the receiver shut down. The run away situation you encountered was one of the two possible outcomes i read about.
http://www.spektrumrc.com/Articles/HobbyWire.aspx
Scroll down to
Simple Fix for Module "Shut Down" Issue
11/02/05
Ensuring you have a good power pack for your radio gear is critical. Recommended is 2000mAh+ and use a Y splitter cable to power your steering servo instead of power being sent to the receiver then having to dish out enough power to run all your servos. I recall that being a potential issue as well. You just plug the battery into the Y spliter, one lead goes to the steering servo the other half of the Y goes to the steering servo socket on the receiver and powers your receiver and throttle servo without the poor little receiver having to supply power to those chunky high power servos.
Lastly do yourself a favor to save yourself some trouble in the future. Open your Spektrum receiver and reroute the antenna out the side hole. When routed out the top there is not support for the antenna lead at all so it's possible to be torn off easily. Run it out the side hole and the receiver casing will provide some stress relive and more safety as it clamps down on the antenna and prevents it from being pulled out any further then you allow it.
Hope this helped.
Crash Dummy.