I have a GE Monogram 4-burner gas range with center griddle. It is about 5 years old and the griddle stopped working. The gas burners all work just fine. We have had 2 certified GE repairmen out but neither seems to have a clue-the second one told me it would have to be ripped from the countertop to be serviced. Following online advice I found here, I did manage to locate and replace the igniter but it still does heat up when I turn on the griddle. I'm at a loss of what to check next. Any ideas would be appreciated.