Dorman 604-110 HVAC Blend Door Actuator - Main

HVAC Blend Door Actuator for GM Applications

This Dorman HVAC blend door actuator is built for specific GM and related vehicle applications that use a main mode door with lever-style operation. It is engineered to match the fit and function of the original HVAC heater blend door actuator, helping restore proper air distribution inside the cabin.

Use Dorman part number 604-110 when servicing a Chevrolet Trailblazer, GMC Envoy, or related platform vehicle with the listed main position fitment.

Key Features

• Rotary switch activation type for HVAC mode control
• Plastic housing construction
• Direct replacement for the original blend door actuator on listed vehicles
• Designed for main HVAC position applications
• Packaged as an actuator only
• Cross-reference part number: Standard Ignition ADR157

Detailed Description

Dorman 604-110 is an HVAC heater blend door actuator intended for vehicles that use a rotary actuator to control the blend or mode door. It is precision-engineered to match the quality and performance of the original actuator on specific years, makes, and models, helping maintain correct airflow direction and temperature control. This part number 604-110 is commonly searched for Chevrolet Trailblazer, GMC Envoy, and Saab 9-7x HVAC repair applications.

Compatible With: Fits 2003-2009 Chevrolet Trailblazer, Main; Fits 2003-2009 GMC Envoy, Main; Fits 2005-2009 Saab 9-7x, Main; Fits 2003-2008 Isuzu Ascender, Main; Fits 2004-2007 Buick Rainier, Main; Fits 2003-2006 Chevrolet Trailblazer EXT, Main; Fits 2003-2006 GMC Envoy XL, Main; Fits 2004-2005 GMC Envoy XUV, Main; Fits 2003-2004 Oldsmobile Bravada, Main.

Common Repair Symptoms

• Incorrect air outlet selection from the dash vents
• Temperature changes that do not respond as expected
• HVAC mode door movement problems
• Clicking or inconsistent actuator operation behind the dash
• Loss of proper cabin airflow routing in Trailblazer, Envoy, or Bravada HVAC systems

Installation Notes and Tips

Verify the vehicle year, make, model, and main position before installation. This actuator is specified for applications with lever-style mode control, so compare the original unit’s connector and mounting style before replacement. After installation, cycle the HVAC controls to confirm smooth operation and proper mode-door response.

Quality Assurance

Dorman designs this actuator as an OE-style replacement for the listed applications, with construction and operation intended to align with the original part on the specified vehicles. For buyers searching 604-110 for Chevrolet Trailblazer or GMC Envoy HVAC repair, this part provides a direct-fit service option for the confirmed fitment list.