There is the power transformer used in this cooktop. You have to check for 120 VAC between the two brown wires (primary winding) and for 12 VAC between the red & the white wires and for 240 VAC between the red & the brown wires (secondary windings).
Also you have to check for continuity the ignition switches and their wire harness.
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Here are the breakdown diagrams and Parts for GE ZGU384NSM2SS Cooktop - AppliancePartsPros.com