38094 Hiawatha runs poorly

TMCC locomotives don't have back driveable gears, so you can't turn the wheels without power.

Did you try turning the motor flywheel by hand with the drive wheels suspended?  It should turn smoothly with no binding through a complete rev of the drive wheels.

It has fan driven smoke, so the fan isn't running.  Do you get chuff sounds?  If so, it has a "smart" smoke unit, I'd be looking around there for the reason you don't get the puffing smoke.

Thanks for the suggestions.

Flywheel turns smoothly and freely, and the drivers make a full revolution without binding.  What should be checked next?  I did not observe any binding in the drive rods.

Chuff sounds work, so not sure what is meant by "looking around there" on the smart smoke unit.  I did notice that one of the two screws that hold the smoke unit in place was missing, for whatever that's worth.

Here's a wiring diagram, see if the chuff signal is actually making it to the smoke unit from the chuff switch.

Unit has a smoke driven fan unit, so check that the fan is spinning.  If not may be the 5V motor regulator, bad motor, or binding.  Pull the motor driver harnesses and reinstall.  Check motor magnet on flywheel for cracks.

But the first think to do is do a R2LC reset with the code from the manual.  G

Thanks.

Any further ideas regarding the stopping and starting above 11 volts?

Did you do the R2LC reset?  After the thoughts above time to start swapping components to find the issue.  G

I don't have command control, and the manual only gives instructions for resetting via TMCC.  I use a conventional AC transformer - is there another way to reset?  And unfortunately, I don't have components to swap in and out.

Thanks for the ideas, but unless there's another brainstorm for making it run smoothly, I think it's time to send it off to the local repair guy.