No crank!

[Massey convert]

I have a Massey 2605H, (about five years old with a Perkins clone), that seems to be in "limp-mode". I was using it Saturday in the woods for several hours, sometimes running the saw, sometimes using the tractor, it was operating normally until I tried to start it after a few minutes of it being shut off, then it would not crank. I checked the transmission and the PTO safety switches, and eventually used a jumper on the wiring harness plugs, and still no-crank. I checked all the fuses under the hood, all good, the same with the relays. The glow plug indicator lights, then goes off like normal, still, no-crank. I walked home and checked the service and owner's manuals for trouble shooting advice, neither were very comprehensive.
Sunday I hauled some tools out there and eventually shorted the starter solenoid to get the starter to crank the engine, while having the key switch on. It starter, but after about 30 seconds slowed, then shut off. After several cycles of that, I found that if I pushed the throttle fully wide open, the engine would run (at idle speed) longer before slowing and shutting off again. I found that when I put it in gear and drove it , it would remain running as long as I left it in gear and drove it, which is how I got it home. As I was driving it home, I noticed the check-engine-light was on and it had limited power and engine speed, "Limp Mode"?
Is some sensor sending the ECM data causing it to revert to "Limp-Mode"?
The temperature was in the twenties F., the fuel has been treated with Power Service Diesel Fuel Supplement, so I doubt that the fuel has gelled.

 

[Massey convert]

Thanks in advance for your help!

 

[Williy]

Have you checked your cables? Test with ohm meter
to see if they haven't rotted out and make sure the
connections are clean. Does it have a regen?
Did you check the code?

willy