When you set temp. say at 400,it will beep to tell you it is now preheated,but temp is only 375.We put temp. gauge in oven to see what temp was. When it gets to desired temp it will drop temp then go back up.It will maintain constant reading.
You can adjust the oven temperature within 35° range. Follow the instructions on page 20 in the Use and Care manual.
Here are the breakdown diagrams and Replacement parts for General Electric JBP75GS1AD Electric range | AppliancePartsPros.com
Gene.