Pitt,
Internal transmission speeds are
indicating there is system
pressure present, although
pressure should NOT be there.
Speed sensor failure. Total
Neutral Solenoid failure. Too
much drag because of thick oil.
Sticking or burnt clutch.
Controller reverts to a Shut
Down Mode and will deactivate
the total neutral solenoid.
Check the wiring between
the controller and the speed
sensors. Check the speed
sensors, Check the speed
sensor positions. Check the
Total Neutral Solenoid.
Check oil quality.
For the engine code, nothing could be found. Do you have an LPG or Cummins diesel? You can find the Cummins codes online. Will need serial number to be more specific. Good Luck.