My wife never considered turning on 2 burners on the same side before the spark module failed. When the module was replaced and the sparking continued with only one burner on I checked the spark gap and looked for evidence of a food or grease build-up around the burners, etc. Everything looked clean and I couldn't find any evident problem. I then tried combinations of burners and found that if both on one side are on, the sparking stops. If one gets turned off the sparking starts again. There have been a very few times that I could turn on both and then turn one off and the sparking would not start, but I can't get it to consistenty do that.
these are the switches, the switches are #323 on this diagram. hope this helps, thanks Bryan
link for part, http://www.repairclinic.com/SSPartDetail.aspx?s=t-+JGSP30GEP2-%3d%3dei244994&PartID=244994