Pierre, I believe it is time I realign some of your misconceptions about your dishwaher. first, read the user manual. It specifically states you are to run the tap at the kitchen sink before you turn on the machine. Secondly, the heating element, MAY be energized during prewash, but it doesn't heat the water but 3 to 5 degrees F during the prewash. There is no thermostatic hold to raise the temperature. The main wash will heat the water to a certain temperature, but atht depends upon options selected when you use smart wash. and incidentally, when you use either high-temp or sani-rinse with the smart wash programme, you cmopletely negate all intelligence of the cycle. the programme defaults to a speficied program sequence without any variance. the final rinse water is also thermostatically held/heated to a set point. I let SmartWash do what it was designed to do, let it select all variables to clean the load, be it water changes, water temperaturs and cycle length. The ONLY US. designed dshwasher that had a temperature delay hold for a pre-wash was the Whirlpool PowerClean and Kenmore UltraWash dishwashers when the Pots/Pans, PowerScour cycle was used.
Now as far as your comment about the older D&M Kenmores with the water temperature sequenced lights, the machine started out with "cool" light being lit. there were a total of 3 water changes prior to the main wash. And if the household water heater was set at 140 or 150 degrees, then by the 3 water change, the light had changed form "cool" to "normal". that is where it stayed unless you used the sani-Rinse option or Sani-Wash cycle. Then, it delayed the timer advance on the final rine until 155 degrees was met. the nomral and delay light would be lit until the 155 temp reached and then the sani light would light up.