Open the door of the oven and find the oven sensor. Typically, this sensor is located in the upper right-hand corner of the oven.
Unscrew the screws that attach the temperature sensor to the oven. Gently pull the wires away from the oven until the piece of plastic that connects the larger wires to the sensor wires detaches from the oven.
Press the small button on the connector to unhook the wires.
Attach the sensor to the ohmmeter. Measure the resistance. It should show about 1100 ohms. If it shows significantly more or less than this, the sensor requires replacement. If you are certain that your sensor is broken, you do not need to measure its resistance.
Open the oven door. Remove the small screws that attach the sensor. Set these screws aside. Remove the sensor and set it aside.
Locate the temperature probe inside the sensor. This probe is typically behind the sensor but the specific location varies by model. Check the owner's manual for specific instructions. Most manuals include a diagram of all of the parts of the oven.
Turn the probe counter-clockwise to unscrew it. Discard the probe.
Place the new temperature probe onto the knob and turn it clock-wise.
Replace the sensor and screw it into the oven using a screwdriver.