My Kohler 17RES has stopped doing it's scheduled weekly exercise. How can I get it exercising again?

Emergency shutdown operation is required when one of the above conditions occurs in diesel generator set.Diesel generating set itself has an emergency stop button, at this time, press the emergency stop button or quickly press the stop control handle of fuel injection pump to the stop position, the diesel generator will quickly cut off the load, and immediately close the throttle, while the red "emergency stop" light is on. Need to press the button again to delete the emergency stop signal. If there are serious faults or distribution faults, you can also press the button on the control panel, and the unit will stop immediately.

In fact, all faults always give operators some warning signal before spare parts break down or engine damage occurs. So the operators need to be smart, and notice alarm signals (sudden drop in oil pressure, abnormal sound, etc.) and immediately stopping the engine.
Emergency shutdown operation is different from normal shutdown operation.
Emergency shutdown operation.Once the operator finds that there is a serious fault or distribution fault in thediesel generating set, he can press the emergency stop button of the control panel to stop the unit immediately. If there is no special circumstances, we advise users not to stop the unit at will through the emergency stop button.

Are there any faults listed on the control display? If display is dark then likely a battery issue. Check battery voltage with a Digital Multi Meter (DMM). It should be at least 12.5VDC.

You will likely need to reference your instruction manual for that specific control panel.

It is most likely set to exercise once a week and run for about 1/2 hour or so

The UV code has nothing to dow ith oil, poor oil would cause under frequency (low engine speed) Under voltage is caused by excessive load, short in the rotor/stator excition system, and/or AVR automatic voltage regulator. Of course loose wiring to will also cause it.

On exercise it isn't under load, you may have too much gas pressure, have the gas pressure and fuel/air ratio checked on the mixer

Product manual does not have troubleshoot section.
The operation might be normal, and within expected parameters, or it might have a glitch.
Suggest you contact Kohler Power directly:
http://kohlerpower.com/contactus/contactus.htm?sectionNumber=

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

I advise you to combine Pilates as your weekly routine, most trainers will tell you that you should exercise three to four times a week but I can tell you that I have a very tight schedule and two workouts a week is more than enough for me.