How to Troubleshoot & Replace Whirlpool AP6278047 / W11122006 Infinite Switch (Top Burner Control)

Replaced the infinite switch with a switch model very similar to the existing switch 

Ordered one from you guy's. I installed it and it works great. This range is 30 years old and you had the switch I needed. Received in 2 days as promised and I had installed in less than 30 minutes. This range started life as a Roper, name fell off then a Magic Chef, made by Admiral and I bought a Whirlpool switch. 

Switched working 8" CalRod with the CalRod that does not give the right heat on Low, Medium and High setting, still won't give the right heat. Borrowed the working switch and installed it to the suspected defective switch. It works fine.So, it is confirmed that the CalRod switch is defective. By the way before I did the switching of CalRod and CalRod switch, I replaced first the CalRod receptacle because the contacts are badly burned. Hope this info help. Thank you.