Toyota Avalon A/C light inoperable, clutch not engaging despite control head replacement on Toyota Avalon

Some Toyota Avalon owners report experiencing issues with the A/C light being inoperable and the clutch not engaging, even after replacing the control head. These problems may stem from various electrical issues that prevent the A/C compressor clutch from functioning properly. Additionally, low refrigerant levels can hinder clutch engagement, while potential problems with the compressor or the clutch itself could also be at fault. Some owners find that a failure of the HVAC control module, commonly referred to as the "AC amplifier" or "A/C ECU," may contribute to these issues. Furthermore, the presence of a B1479 Flow Control Circuit trouble code could indicate a malfunctioning refrigerant flow control sensor affecting clutch operation. To effectively diagnose and resolve these concerns, a thorough inspection of the relevant components and systems is recommended.