Microwave displays SE or "Sensor Error" during sensor cooking modes and stops the cycle.

Safety: Disconnect power before accessing internal components.

• Clean the cavity: Wipe down the interior of the microwave, especially the area near the sensor port (often on the upper cavity wall), with a mild detergent and soft cloth. Remove grease and food residue.
• Allow to dry: Leave the door open and allow the cavity to dry completely, then test a sensor cook function again.
• Inspect sensor: Locate the humidity / steam sensor behind the cavity wall. Check for damage or loose connections on its harness.
• Test sensor: Using the Monogram service manual, measure the sensor's resistance or voltage response if specified. Replace if out of range.
• Replace sensor: If cleaning and wiring checks do not resolve SE, replace the humidity sensor with the correct Monogram part. If the error persists, the electronic control board may be defective.