Magic Chef oven displays F3 and may stop heating; sometimes appears shortly after starting a bake cycle.

Safety first: Disconnect power at the breaker before accessing internal wiring or the rear panel.

• Access the sensor: Locate the temperature sensor inside the oven on the rear wall. Remove the mounting screws and gently pull the sensor forward to access the connector.
• Test the sensor: Disconnect the sensor and measure resistance with a multimeter. At room temperature, it should be around 1050–1100 Ω. If it reads open (OL), near 0 Ω, or far from spec, replace the sensor.
• Inspect harness: If the sensor tests good, follow the harness to the EOC (from the rear of the unit). Look for pinched, burnt, or broken wires. Repair any damage and ensure connectors are fully seated.
• Check at the EOC: Measure resistance at the EOC sensor terminals with the sensor connected. If readings differ from the sensor directly, the harness is faulty.
• Replace EOC if needed: If sensor and wiring are good but F3 persists, the EOC’s sensor input circuit may be defective. Replace the electronic oven control board.

When to call a technician: If you lack a multimeter or are not comfortable removing the oven from the cabinet, consider professional service.