Troubleshooting Jenn air cooktop issue
If the breaker pops when you turn on a specific burner, even if the cartridge is not plugged in, chances are that burner control switch has gone bad.  The power on those units goes through the four burner controls before going out to the cartridge sockets.

I had one that if turned on to any setting, would just run the burner on high.

If you can depower the unit, then you could run some continuity tests, so see if the burner control is shorting.  The controls are not a simple rheostat, but some form of high current modulator.  Off the top of my head, a replacement runs around $60.  I think I found someone selling them on eBay.