Replacement of dual infinite switch 12002125 vs 7403P406-60.

SOURCE: I ordered a replacement switch

There was a design change related to this switch. I had the same problem earlier today and figured it out by getting the schematics from searspartsdirect.com. There are two different schematics there (in English). The old schematic is labeled "DIAGRAM NO. 8104P688-60". The new one has five notes in the lower left (that don't help). The key is to split out the red wire coming back from the double burner element. The old way had it connected to "N" along with the RED source power. The new way has it connected to terminal "2" all by itself with the RED source power now connected to terminal "P2". But in addition, you have to add an extra jumper wire that should have come with your new switch that goes from "P1" to "S1". The other connections simply move from the old switch to the new where the locations can be seen on the schematics by referencing the wire colors (example: TAN wire moves from the old "3" to the new "4", etc.). If you are not 100% sure of what you are doing - you shouldn't try this. A wrong wire in the wrong place can short out 240V when you throw the breaker (boom!). Good luck. -- Mark.

SOURCE: I need instructions for wiring in replacing a dual burner switch

We followed the instructions that came with the switch that addressed a "compound wiring" configuration. We also used the black jumper wire as shown in the instructions.
We got to this solution in a trial by error manner though, because the three of us working the problem were convinced the stovetop was wired in a "piggyback configuration" and tried that road first. It would have been helpful if the instructions had included an explanation of the switch manufacturer's interpretation of "compound" and "piggyback" configuration.