If the rear element works the first thing to check is the wiring at the 3 in one front element, these wires often break where they bend, and there is a common black wire that will stop all three elements from working.

Note, that wire trivet should never be used on an electric range if you are using a setting that allows the element to get red hot, doing so is dangerous and ruins the elements on your beautiful range,

If you want to use Pyrex on an electric range either use a lower heat setting or place the Pyrex on the element when cool and then turn on the element, setting Pyrex directly on a red hot element could break it, and of course you don't need a trivet with Corning ware, it can be set directly on a red hot element with no chance of damage ever.

John L.

John L.