Electrolux Range Error Code LEDs 4,5

LEDs 4 and 5 on an Electrolux range indicate an open circuit in the oven temperature probe loop. The oven temperature probe is a resistive temperature sensor, typically an RTD (resistance temperature detector), that the electronic control board uses to monitor oven cavity temperature in real time. When the control board detects that the resistance in the probe circuit is excessively high or infinite, it interprets this as an open circuit and triggers this fault condition. A properly functioning probe should read between 1050 and 1100 ohms at room temperature.

An open circuit in this loop can originate at several points: the probe element itself may have failed internally, the wiring harness connecting the probe to the control board may be damaged or disconnected, or the terminals at either end of the circuit may be corroded or loose. Because the control board continuously monitors probe resistance to regulate oven temperature, an open circuit effectively blinds the board to any temperature feedback, making safe oven operation impossible.

Diagnosis begins by measuring the resistance across the probe's terminals with a multimeter. A reading outside the 1050 to 1100 ohm range at room temperature confirms the probe has failed and needs replacement. If the probe resistance is within spec, the fault lies in the wiring between the probe and the control board, or in the control board itself. In that case, after ruling out wiring issues, the electronic control board is the likely failed component.