Thanks for taking the time to respond HogMike.
What do the service instructions give for testing the correct trigger temperatures for the two scenarios. The method describes confirmation that both options work but does not appear to confirm they work at the required temperature.
Your information is useful though, I did not know that the fans or cylinder cutout could be initiated manually.
JohnT
To find out if the fan(s) come on at the set point(s), eitms, in the ecm you will have to be able to monitor the engine temp, inlet air temp, ambient air temp, idle rpm, and probably a couple other sensors I forgot about.
This would require hooking up Ditigal tech, TTS, or a few other devices to monitor/control settings.
For example, on my M8 my settings for the radiator fans are a little different from factory settings because of where I live and my larger motor (more heat generated). These things can be monitored and controlled to a certain degree with the proper ecm access.