Whirlpool LF dual element temperature control

The LF element on my Whirplool Gold Accubake (Convection) smooth top range has been acting up - dual element will only work for "large" and temperature is always high. Ideas on what to replace are welcome?

The problem can be a bad infinite switch for this burner as well as a bad heating element. Both parts must be tested.

This is the Canadian model and we do not have diagrams and/or part numbers for this model number.

Gene.