GE Oven Error Code F33

F33 on a GE oven means the control board has detected that the lower oven sensor circuit is reading a resistance value outside the acceptable range. The board monitors this resistance to determine oven temperature, and when it falls outside expected thresholds, it flags the fault and interrupts normal operation. The sensor probe, the wiring harness, or the connector at the control board are the most likely sources of the problem.

Using the oven while F33 is active is not recommended. The error means the control board cannot reliably read the lower oven temperature, which means the oven may overheat or fail to reach and hold the correct temperature without triggering any safety shutoff. Operating the oven in this condition risks food safety issues and potential damage to the appliance.

Unplug the oven and disconnect the sensor from the wiring harness. Set a multimeter to the ohms setting and measure across the two sensor terminals. At room temperature, a good GE oven sensor reads roughly 1080 to 1100 ohms. A reading near zero indicates a shorted sensor, while an infinite or very high reading indicates an open sensor. Either condition confirms the sensor needs replacement. If the sensor reads correctly on its own but the error persists, measure resistance at the connector pins on the control board to identify a wiring issue.

Start by measuring the resistance of the lower oven sensor circuit at ERC connector CN300 pin 1 to 8 (W to W/R) or at Machine Control lower oven board connector J300 pins 1 to 2. A healthy sensor reads approximately 1080 to 1100 ohms at room temperature. If the reading is far outside this range, replace the lower oven sensor. If the sensor reads correctly at its own terminals but not at the board connector, inspect the wiring harness for breaks or burns and check the connector pins for corrosion or looseness.

If the lower oven sensor is the cause, replacement sensors are typically priced between $20 and $60 for the part, and the repair is manageable for a careful DIYer since most sensors are secured with one or two screws and connect via a simple harness plug. If the wiring harness needs repair or replacement, parts and labor can run $100 to $200. A control board replacement is the most expensive scenario, with boards often costing $150 to $350 plus labor if you use a technician.