Four Seasons 73634 HVAC Blend Door Actuator - Auxiliary or Left

Four Seasons 73634 HVAC Blend Door Actuator

The Four Seasons 73634 HVAC blend door actuator is a direct-fit replacement for vehicles that need precise control of cabin air temperature and airflow direction. Built for applications such as the Infiniti QX80, Nissan Armada, and Nissan Pathfinder, it helps restore proper HVAC door movement when the original actuator wears out or fails.

Key Features

• HVAC air door actuator style for blend door control
• Male door linkage for direct mechanical engagement
• 4 mounting ears for secure installation
• 3-terminal pin electrical connection
• Four Seasons part number 73634 for easy identification

Detailed Description

Four Seasons 73634 is an HVAC blend door actuator engineered and tested for dependable operation in climate control systems. It is used in auxiliary and left-side No. 2 applications across select Infiniti and Nissan models, including the Infiniti QX80, Infiniti QX60, Infiniti QX56, Infiniti JX35, Nissan Armada, Nissan Pathfinder, and Nissan NV3500. This part cross-references 277323JC2A and 277421LA1A for the same application. If you are searching for a blend door actuator for a 2014-2024 Infiniti QX80 auxiliary HVAC system or a 2013-2020 Nissan Pathfinder left No. 2 position, this part number is a direct reference to verify before ordering.

What It Helps Fix

• Incorrect cabin temperature from a stuck blend door
• Airflow that does not change between hot and cold settings
• HVAC doors that stop responding to control inputs
• Temperature inconsistency in auxiliary climate zones
• Noise or erratic movement from a failing actuator

Installation Notes and Tips

Confirm the position, connector style, terminal count, and mounting ear layout before installation. This actuator is listed for auxiliary and left No. 2 applications only, so match the vehicle year, make, model, and HVAC position exactly. For best results, inspect the blend door and surrounding HVAC components for binding or damage before replacing the actuator.

Quality Assurance

Four Seasons backs this part with more than 50 years of mobile A/C experience and states that its products are engineered and tested for years of trouble-free operation. The 73634 is built to support reliable HVAC performance in the listed Infiniti and Nissan applications.