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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1413 (HVAC SYSTEMS - AUTOMATIC)COMPONENT LOCATORHVAC COMPONENT VIEWS

2003 Chevrolet TrailBlazer 4.2 S, 4WD

HVAC Component Views

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION HVAC Component Views

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Six Cylinder Engine, Left Side HVAC Component View

GM747710

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	A/C Compressor Clutch Connector
2	A/C Compressor

Fig 2: Ambient Air Temperature Sensor

GM747711

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Ambient Air Temperature Sensor

Fig 3: A/C Refrigerant Pressure Sensor, Six Cylinder Engine

GM797101

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Air Conditioning Refrigerant Pressure Sensor
2	A/C Compressor

Fig 4: A/C Low Pressure Switch

GM747714

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	A/C Low Pressure Switch

Fig 5: Accumulator & Coolant Bypass Valve (Long Wheelbase Except XUV)

GM825659

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Accumulator
2	Coolant Bypass Valve

Fig 6: Instrument Panel Carrier HVAC Components

GM747715

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Blower
2	I/P Center Support
3	Blower Motor Control Processor
4	Blower - Auxiliary (Short Wheelbase and XUV)
5	Air Temperature Actuator - Left

Fig 7: Lower Air Temperature Sensor - Right Side

GM747716

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Lower Air Temperature Sensor-Right

Fig 8: Lower Air Temperature Sensor - Left

GM747731

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Lower Air Temperature Sensor-Left

Fig 9: Instrument Panel Carrier HVAC Components, Left and Right

GM747718

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Air Temperature Actuator-Right
2	Air Temperature Actuator-Left
3	Defrost Actuator
4	Mode Actuator

Fig 10: Recirculation Actuator, Cowl Side

GM747719

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Recirculation Actuator

Fig 11: Upper Air Temperature Sensors - Air Duct

GM747721

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Upper Air Temperature Sensors

Fig 12: Ambient Light/Sunload Sensor

GM747798

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Ambient Light/Sunload Sensor

Fig 13: HVAC Control Module

GM747722

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	HVAC Control Module

Fig 14: Blower Motor & Control Processor - Lower I/P, Right Side

GM891676

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Blower Motor Control Processor
2	Blower Motor

Fig 15: Front Auxiliary Blower Motor Switch (Long Wheelbase Except XUV)

GM826160

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Lower Console
2	Blower Motor Switch - Auxiliary

Fig 16: Inside Air Temperature Sensor (B-Pillar, Left)

GM747723

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Inside Air Temperature Sensor

Fig 17: Lower Console HVAC Components

GM872448

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Lower Console
2	HVAC Control Module-Auxiliary or RSA/HVAC Control Module-Auxiliary
3	Console Mode Actuator
4	C309
5	C307

Fig 18: HVAC Module - Auxiliary (Long Wheelbase Except XUV)

GM872310

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Mode Actuator - Auxiliary
2	Blower - Auxiliary
3	Air Temperature Actuator - Auxiliary
4	C401
5	In-Line 30A Fuse

Fig 19: Blower Motor Control Processor - Auxiliary (Long Wheelbase Except XUV)

GM1208964

Courtesy of GENERAL MOTORS CORP.

Callout	Component Name
1	Body Rear Opening
2	Blower Motor Control Processor - Auxiliary
3	Rear Evaporator and Heater Core

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.