Four Seasons 73742 HVAC Mode Door Actuator

HVAC Mode Door Actuator for Defrost Control

The Four Seasons 73742 HVAC mode door actuator controls air distribution for the defrost position in select Volkswagen and Audi vehicles. Built as an HVAC air door actuator with an arm-style door linkage, it supports precise movement of the mode door for consistent cabin airflow control.

Compatible with 2006-2017 Volkswagen and Audi applications, including Volkswagen Jetta, Eos, R32, Tiguan and Audi A3, TT, TTS Quattro, TT Quattro, TT RS Quattro, and A3 Quattro, this part number 73742 is a direct-fit replacement for the defrost mode door function.

• HVAC mode door actuator for defrost air distribution
• Arm-style door linkage for mode door movement
• 3 mounting ears for secure installation
• 5-terminal pin electrical connection
• Four Seasons part number 73742

Detailed Product Overview

Four Seasons 73742 is engineered as an HVAC air door actuator for vehicles that use electronic control of the defrost mode door. The actuator’s arm linkage and 5-pin terminal design support accurate door positioning, helping the HVAC system route air where it is commanded by the control head. This part cross-references select OE and aftermarket numbers such as 1K0907511E and 1K1907511E for the same application.

Use this actuator on fitments such as 2006-2014 Volkswagen Jetta, Defrost; 2009-2016 Volkswagen Eos, Defrost; 2008-2014 Audi TT, Defrost; and 2006-2013 Audi A3, Defrost. The Four Seasons 73742 is also listed for 2017 Volkswagen Tiguan, Defrost, along with related Audi TT Quattro, TTS Quattro, TT RS Quattro, and A3 Quattro applications.

Common Problems This Part Addresses

• Defrost vents do not respond when the HVAC controls are changed
• Airflow stays stuck in one mode position
• Weak or inconsistent movement of the mode door
• HVAC control commands do not match vent output
• Clicking or binding at the defrost actuator location

Installation Notes and Tips

Verify the connector style, mounting ear layout, and door linkage style before installation. Confirm the vehicle’s HVAC system is calling for the defrost position and compare the existing actuator to Four Seasons 73742 to ensure the correct fitment for your Volkswagen Jetta, Audi A3, or related model. After installation, cycle the HVAC controls through the available modes to confirm proper door movement and defrost operation.

Quality Assurance

Four Seasons backs this HVAC actuator with more than 50 years of mobile air conditioning experience. The brand states that its products are engineered and tested for years of trouble-free operation, with a focus on repairing the system correctly the first time.