Coils would not heat up unless both control swithes were on high

I always wanted an extra cartridge for my stove. The grill it came with never got used. Now I have a 4 burner stove. However I need to look at the control switches. The brand new cartridge works the same as the old one did. I figured this would be the case.
Parts Select did a great job getting me the insert. Now I need to order up the switches. Hopefully them we will be back in business. More trouble shooting on the way...