Indoor unit shows F1 and may stop or run erratically; temperature control is inaccurate.

Safety first: Turn off power at the breaker before removing covers.

• Locate room sensor: The indoor ambient sensor is usually clipped near the air intake or behind the front grille. Carefully remove the front panel to access it.
• Check connection: Ensure the sensor plug is firmly seated on the indoor PCB and that the wires are not cut or pinched.
• Inspect sensor body: Look for physical damage or corrosion. If the sensor is cracked or discolored, it should be replaced.
• Replace sensor if needed: Order a Haier-compatible indoor ambient temperature sensor and swap it, matching connector type and mounting position.