Safety: Disconnect power before accessing the control housing or sensor wiring.

Steps:

Locate the ambient sensor: On models with an E7 code, the ambient thermistor is often located near the control panel or in a small vent on the front/top of the cabinet.
Visual inspection: Check for broken wires, sensor pulled out of its holder, or signs of moisture intrusion.
Test the sensor: Disconnect the sensor from the harness and measure resistance at room temperature. Compare to the expected value from the tech sheet (commonly 5k–10kΩ at 77°F). An open or shorted reading indicates a bad sensor.
Check harness continuity: Verify continuity from the sensor connector to the main control board connector. Repair any damaged sections.
Replace the ambient sensor if faulty: Install the new sensor in the same location and route the wires neatly, avoiding pinch points.
Power up and verify: Plug the freezer back in and allow it to run. The E7 code should clear once the control sees a valid ambient reading.

Tip: If the sensor and wiring are good but E7 persists, the control board’s sensor input circuit may be defective.

Magic Chef freezer shows E7 and interior temperature fluctuates widely or does not match the setpoint.

Possible Causes