Whirlpool dryer same heat on all settings

My electric dryer seems to run with the same heat whether I select the low, medium or high setting. I measured the temp (using an oven thermometer on the dryer rack) at 150 degrees F on all three levels. Which parts would I test (I do have an ohm meter) for possible replacement?

Separately the timed cycle does not work. The dryer randomly shuts down during the cycle as if the time is complete. This sounds like a problem with the timer mechanism? The sensor cycle does work although I usually have to select "most dry" to get any load of clothes to dry.