Eric,
You have done a wonderful job of gathering all of the ASR problems in one page. My '93CE doesn't have a throttle position switch that anyone can find but it does have mis-matched tires. Also, I never get the "ASR" light but this could be indicative of the '93's.
I also live in the desert but will take a look at the temperature switch. The car started off in Florida but spent the last 4-5 years in San Diego. I've contacted the previous owner to see if she ever had this "problem". If "no", then it has to be the new alternator that was replaced right before I picked up the car.
Anziani
'93 300CE
'95 E420