kenwood kdw 243a?

I have a kenwood kdw 243a that shows E3, I tested the element and shows ok, i joined the 2 pink wires up going to temp switch on the right side at bk and worked great , so bought the 78 and 90 temp switches to make sure both were good, but after replacing both it still shows up E3 and beeps and wont do nothing unless i join the wires up and then it works great , can anyone give any advice please ,many thanks