Self-cleaning feature of GE Built-In Oven does not...

Question

All cooking functions work properly. Self-cleaning function does not work.
With oven temp k**b set to clean, start and stop dials properly set, the latch handle properly set and the oven set dial set on clean, the oven will not self-clean. The oven cycling light above the oven temp k**b does not
come on. Should I replace the controller mechanism behind the oven temp
k**b or should some other part be replaced ? Thank you. Bob