Kitchen Gas Appliances - Amana burner not igniting

I own a relatively modern Amana 3660 gas cooktop. One of the burners refuses to ignite when using the knob. In the dark, one can see that there is no "spark" to that burner. The burner easily operates well if you use a match to start it, no gas problem. How does one differentiate which component failed? On the diagram, it shows the spark igniter and two burner igniter electrodes which may be the cause. Does it make sense to start with the spark igniter?

It sounds as if the piezo probe has grounded out. Possibly cleaning the unit someone inadvertently hit the probe and it is touching the metal adjacent to it. Take a close look at the probe to see if that isn't the case. Let us know.