The temperature on the display is jumping around rapidly

This may indicate a loose temperature sensor connection. For 700 models, check the cable connection between the grill and the controller. For 700 or 450A models, disconnect the power, remove the two screws on the front of the controller, and gently pull the controller forward. You will see two skinny white sensor cables, which should be tightly secured into the blue or green terminal block. If they are loose, the temperature reading may be inaccurate. If none of these steps solve the issue, please contact us.