Frigidaire air conditioner displays E2 and may shut down cooling; fan may still run intermittently.

Safety: Disconnect power before opening the cabinet. Sharp metal edges are common inside window and through-the-wall units; wear cut-resistant gloves.

Steps to diagnose E2:

• 1. Power cycle: Unplug for 5–10 minutes and restart. If E2 reappears quickly, proceed.
• 2. Access the evaporator section: Remove the front grille and filter. Remove any screws securing the front cover to expose the evaporator coil (the cold coil at the front).
• 3. Locate the evaporator sensor: Look for a small probe or clip-on sensor attached to the evaporator coil tubing with two wires leading back to the control board.
• 4. Inspect wiring: Check for broken insulation, pulled wires, or a loose connector. Reseat the connector at both the sensor and the control board if accessible.
• 5. Test the sensor: Disconnect the sensor and measure resistance at room temperature. Compare to the specification in the service manual (often similar to the room thermistor). If the reading is open, shorted, or far out of range, replace the sensor.
• 6. Replace sensor: Install a Frigidaire-compatible evaporator temperature sensor, clipping it firmly to the same coil location. Ensure the sensor is in good contact with the tubing.
• 7. Evaluate control board: If a new sensor does not clear E2, the main PCB may have a failed sensor input and should be replaced.

Professional help: If you see frost or ice buildup on the coil along with E2, there may also be a refrigerant or airflow issue that requires a licensed technician.