I have a GE oven (model JTP35S P2SS) that is two years old. The top oven won't heat up to the correct temperature. For example, we set it at 350 degrees, it beeps to let us know that it's ready, but the actual temperature is only 250 degrees per an oven thermometer we have placed on the rack. It seems to cycle on/off frequently (based on clicking sound) after it beeps to indicate it has reached the set temperature. If left on it will eventually reach the desired temperature (perhaps 30 minutes later). Adjusting the calibration doesn't change the behavior. I pulled the temperature sensor and tested it with an ohm meter. At room temperature the reading was 1088 ohms. Does this indicate that the control board is the problem or is there another component that could cause this?