Indoor unit runs briefly then stops; display shows E2 and cooling stops.

Safety first: Isolate power at the breaker before removing the indoor unit cover.

• Access the thermistor: Remove the front panel and air filters. The room temperature sensor is usually clipped near the air intake or on the evaporator coil frame, connected by thin wires to the control box.
• Check connection: Ensure the thermistor plug is fully seated on the indoor PCB. Reseat it and inspect for corrosion or broken wires.
• Visual inspection: Look for damage to the sensor body or cut wires. If the sensor is physically damaged, replace it with a Sharp-compatible room thermistor for your model.
• Resistance check (for advanced DIYers): With power off and sensor disconnected, measure resistance with a multimeter. Compare to Sharp’s service chart (typically 5–20 kΩ at room temperature). Infinite or near-zero resistance indicates a bad sensor.
• PCB input fault: If a known-good thermistor still triggers E2, the indoor PCB sensor circuit may be defective and the board will need replacement.