Oven won't heat up, bake or broil. All other functions work.

Frigidaire PLEFZ398GCB - 6 years old Everything was working fine and now both heating element won't work. The surface top and warming drawer work as they should. I do have continuity for both elements. I checked power at the board and there is 120v going to each element and 120v coming out of both elements as soon as I choose bake or broil yet they are barely heating. Should I have 240v there? On the display it shows it changing from top to bottom element, but nothing changes with the voltage. I noticed that the board energizes both elements all the time even if I choose just broil which I would think would only energize the top element. I have 3 wire plug with 120 on each leg and 240v across.