Four Seasons 73728 HVAC Mode Door Actuator - Left

Four Seasons 73728 HVAC Mode Door Actuator

The Four Seasons 73728 HVAC mode door actuator restores precise airflow control in the cabin HVAC system. Built with a gear-style door linkage and a 5-pin terminal layout, it is a direct replacement for select Lexus applications that need accurate mode door movement for proper vent selection.

Key Features

• HVAC air door actuator for mode door control
• Gear-style door linkage for controlled movement
• 4 mounting ears for secure installation
• 5-terminal pin connector configuration
• Engineered and tested for dependable operation
• Four Seasons part number 73728

Detailed Description

Four Seasons 73728 is an HVAC mode door actuator used to position the air distribution door inside the climate control system. In Lexus GS, IS, RC, and RC F applications, this actuator helps direct airflow to the dash vents, floor outlets, or defrost outlets based on the HVAC command. The gear-driven design supports consistent door movement, while the 4-ear mounting pattern and 5-pin electrical interface match the listed vehicle applications. This part cross-references OE-style numbers such as 8710630570 and ACT2078IM for the same application. Four Seasons 73728 is built from the company’s long-standing mobile A/C experience and is intended to deliver reliable HVAC control in the vehicles listed below.

Vehicle Fitment

• Fits 2023-2024 Lexus IS300, Left
• Fits 2023-2024 Lexus IS350, Left
• Fits 2022-2024 Lexus IS500, Left
• Fits 2023-2024 Lexus RC F, Left
• Fits 2023-2024 Lexus RC300, Left
• Fits 2023-2024 Lexus RC350, Left
• Fits 2016-2020 Lexus GS F, No. 1
• Fits 2013-2020 Lexus GS350, No. 3
• Fits 2018-2019 Lexus GS300, No. 1
• Fits 2015-2018 Lexus GS450h, No. 3
• Fits 2014-2015 Lexus IS250, No. 5
• Fits 2013-2014 Lexus GS450h, Type A

Common Problems This Part Can Address

• Airflow stuck on one vent position
• HVAC mode changes that do not respond correctly
• Inconsistent air distribution between dash, floor, and defrost outlets
• Clicking or binding from a worn actuator gear
• Loss of proper cabin comfort control in the climate system

Installation Notes and Tips

Verify the connector style, mounting ear layout, and actuator position before installation. On Lexus GS, IS, RC, and RC F models, confirm whether the application uses Left, No. 1, No. 3, No. 5, or Type A placement as listed. After installation, cycle the HVAC controls to confirm the mode door moves through all positions and the system responds correctly.

Quality Assurance

Four Seasons engineers and tests its HVAC components for long-term operation. Backed by more than 50 years of mobile A/C experience, this actuator is built to support dependable climate control performance in the specified Lexus applications.