Bosh double oven. Temp is 100 degrees cooler on top oven, any ideas? both on bake mode

The fact that top oven is 100degrees less than bottom is no relation between the two; they are controlled by independent stat controls and if the only way you know if the temp is correct, is to set a temp (such as 350 degrees) and put a thermometer in that oven to see if the thermometer is with in 25degrees of the control settting. You need to do this for the bottom oven as well to see if it is aslo within 25degrees of the setting. then you make adjustments for each unit independently. If the controls are mechanical (knob), then the adjustment is within the control (usually by removing knob and serching for a small screw). If the controls are electroonic, then you need to search the circuit board to see if there is adjstments mounted on the board. Goodluck,Macgivor