Update: I went through as much of the diagnostic as I could. Of course, it started with selecting heated seats while you observe the PID on a scan tool. I couldn't figure out how to do this with Forscan. Guessing it's noy possible. If it is, I'd love for someone to enlighten me.
Wire checks all passed. Buttoned it up, thinking I would need a new FICM. Went for a drive and tried the heated seats on more time. Only this time i selected medium instead of high. Pretty quickly my bottom side got warm.
Thought about it for a while. I replaced the Climate Control panel in early fall with a used one because the original was randomly causing the radio to skip through the input modes. The replacement cured that. But thinking back we remember only high and low setting for the seats. We know have 3 heat levels (or lighted dots).
I used Forscan to select the icon that had only 2 positions (lights), but the seats would not heat. Switched it back to Heated seats (the choices i have for icons are cooled only, heated and cooled and heated seats) and it works on medium but not high. Same if i put the heated and cooled icons on the screen.
I can only conclude there is some difference between our original panel and the replacement that I can't account for. Going to called this mostly fixed.
Thank you very much for the documentation HAZ