Heating, Ventilation and Air Conditioning Chevrolet Avalanche I

Fastener Tightening Specifications

Heating, Ventilation And Air Conditioning - Fastener Tightening Specifications

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The Heating, Ventilation and Air Conditioning (HVAC) system is divided into three sections. The first, Heating, Ventilation and Air Conditioning, has all procedures that pertain to a HVAC component or function that are not specifically associated with an automatic or manual control system. The second, HVAC Systems-Manual, has all procedures specific to the manual control system. The third, HVAC Systems-Automatic, has all the procedures specific to the automatic control system.

For systems with DTCs, begin the system diagnosis with the following procedures

1. DIAGNOSTIC SYSTEM CHECK - HVAC SYSTEMS - MANUAL in HVAC Systems-Manual
2. DIAGNOSTIC SYSTEM CHECK - HVAC SYSTEMS - AUTOMATIC in HVAC Systems-Automatic

The Diagnostic System Check will provide the following information

1. The identification of the control modules which command the system.
2. The ability of the control modules to communicate through the class 2 serial data circuit.

The use of the Diagnostic System Check will identify and lead the technician to the correct diagnostic procedure.

Review the Description and Operation information to help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the Description and Operation information will also help you determine if the condition described by the customer is normal operation. The HVAC Description and Operation information is divided into

1. AIR DELIVERY DESCRIPTION AND OPERATION in HVAC Systems-Manual
2. AIR TEMPERATURE DESCRIPTION AND OPERATION in HVAC Systems-Manual
3. AIR DELIVERY DESCRIPTION AND OPERATION in HVAC Systems-Automatic
4. AIR TEMPERATURE DESCRIPTION AND OPERATION in HVAC Systems-Automatic

The Air Delivery Description and Operation contains the following topics

1. HVAC Control Components
2. Air Speed
3. Auxiliary Air Speed
4. Air Delivery
5. Auxiliary Air Delivery
6. Recirculation Operation
7. Automatic Operation

The Air Temperature Description and Operation contains the following topics

1. HVAC Control Components
2. Heating and A/C Operation
3. Auxiliary Heating and A/C Operation
4. Automatic Operation
5. Auxiliary Automatic Operation
6. Engine Coolant
7. A/C Cycle

Tools Required

1. J 39400-A Halogen Leak Detector
2. J 41447 R-134A A/C Tracer Dye-Box of 24
3. J 41459 R-134A A/C Tracer Dye Injector
4. J 42220 Universal 12V Leak Detection Lamp
5. J 43872 Fluorescent Dye Cleaner

Refrigerant Leak Testing

Important: General Motors passenger cars are now manufactured with fluorescent dye installed in the A/C system.

The preferred method of leak testing is the use of fluorescent dye. J 41447 is the only dye approved by General Motors. Follow the Fluorescent Dye Injection procedure for vehicles that do not already contain the fluorescent dye.

Fluorescent Leak Detector

1. Fluorescent dye will assist in locating any leaks in the A/C system.
2. The J 41447 dye mixes and flows with the PAG oil throughout the refrigerant system. Important: PAG oil is water soluble.
3. Condensation on the evaporator core or the refrigerant lines may wash the PAG oil and fluorescent dye away from the actual leak. Condensation may also carry dye through the HVAC module drain.
4. To prevent false diagnosis in the future, thoroughly clean the residual dye from any area where leaks were found. Use a rag and the approved fluorescent dye cleaner J 43872 .

Fluorescent Dye Injection

Important: J 41447 is the only A/C leak detection dye approved by General Motors.

1. Not all of the R-134a dyes are compatible with PAG oil. Some dyes decrease the oil viscosity or may chemically react with the oil.
2. R-134a leak detection dye requires time to work. Depending upon the leak rate, a leak may not become visible for between 15 minutes and 7 days.

Important: Do NOT overcharge the A/C system with dye. This may cause reliability problems. Use only one 7.39 ml (0.25 oz) charge bottle of J 41447 .

1. With the A/C system charged, add J 41447 to the A/C system using J 41459 . Follow the instructions provided with J 41459 .
2. To prevent any false diagnosis, thoroughly clean any residual dye from the service port with a rag and the approved fluorescent dye cleaner J 43872 .
3. The dye injection package contains a notice sticker. Complete the leak detection information and place the sticker near the charge label.

A/C Compressor Shaft Seal Leak Detection with Dye

Use J 43872 to clean all traces of fluorescent dye from the A/C compressor shaft seal and reinspect the compressor.

1. Run the A/C system 15-30 minutes depending on the type of leak in order to circulate the dye.
2. Use J 42220 to inspect the A/C compressor shaft seal.
3. To prevent a future false diagnosis, thoroughly clean any residual dye from the area of the leak with a rag and the approved fluorescent dye cleaner J 43872 .

Service Ports

The sealing cap is the primary seal for the service ports. The cap contains an O-ring gasket that provides a leak-free seal. Install the cap tightly for leak-free sealing. The following conditions will cause a refrigerant loss

1. A loose cap
2. A missing cap
3. An incorrect cap

Use J 42220 or J 39400-A in order to test the service ports and sealing caps for leaks.

To prevent a false diagnosis, thoroughly clean any residual dye from the service port or sealing cap with a rag and the approved fluorescent dye cleaner J 43872 .

Evaporator Core

Use J 42220 in order to inspect the HVAC drain port. Follow the Fluorescent Dye Injection procedure if the A/C system does not contain fluorescent dye.

If only J 39400-A is available complete the following steps

1. With the engine running, turn the A/C ON.
2. Select the maximum blower motor speed for at least 15 seconds.
3. Turn OFF the engine.
4. Turn OFF the blower motor.
5. Wait 10 minutes.
6. Turn ON the blower motor and select the lowest speed.
7. Insert the leak detector probe into one of the center instrument panel outlets. Try to get as close to the evaporator as possible.
8. A solid alarm on the detector indicates a leak.

Halogen Leak Detector

Ensure that the vehicle has at least 0.45 kg (1 lb) of refrigerant in the A/C refrigeration system in order to perform a leak test. Refer to REFRIGERANT RECOVERY AND RECHARGING for recharging the A/C system.

Important: Halogen leak detectors are sensitive to the following items

1. Windshield washing solutions
2. Many solvents and cleaners
3. Some adhesives used in the vehicle

Clean and dry all surfaces in order to prevent a false warning. Liquids will damage the detector.

Important: Follow a continuous path in order to ensure that you will not miss any possible leaks. Test all areas of the system for leaks.

The J 39400-A is a small unit that operates on volts DC. The J 39400-A provides an audible signal that increases in frequency as the unit detects R-134a. Follow the instructions included with the unit in order to properly calibrate the instrument. Use the detector in the proper setting for the type of tested refrigerant.

The most common leaks occur at the refrigerant fittings or connections. The leaks may be the result of any of the following conditions

1. Improper torque
2. Damaged O-rings or sealing washers
3. Lack of lubricant on O-rings
4. Dirt or debris across the O-ring or sealing washers

Maintain a proper scan rate in order to successfully use the J 39400-A or any other electronic leak detector. Carefully follow the manufacturer's instructions regarding the following items

1. Calibration
2. Operation
3. Maintenance

In order to test for leaks, complete the following steps

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1. Completely and slowly circle each joint with the probe.
2. Place the tip of the probe as close as possible to the surface, but no more than 6 mm (0.25 in) away. Do not block the probe tip air intake.
3. A leak exists when the audible tone goes from a steady 1-2 clicks per second to a continuous alarm.
4. Frequently adjust the balance knob in order to maintain the rate of 1-2 clicks per second. Use J 39400-A to inspect each hose connection. Use J 39400-A to inspect all the electrical sensors and switches located in the A/C lines. Use J 39400-A to inspect the service ports. If you know that the system has lost the refrigerant charge and you cannot find a leak using J 39400-A , follow the Fluorescent Dye Injection procedure using J 42220 .

A/C Compressor Shaft Seal Leak Detection with J-39400-A

1. Blow compressed air into the following locations for at least 15 seconds: Behind the A/C compressor clutch/pulley In front of the A/C compressor clutch/pulley
2. Wait 1-2 minutes.
3. Probe the area in front of the pulley.
4. Probe the area behind the pulley.
5. A solid alarm from the detector indicates a leak.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

1. This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.
2. This step measures the performance of the A/C system.
3. This step is to allow for vehicle variations as well as high ambient air temperatures.

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Eliminating Air Conditioning Odor

Odors may be emitted from the air conditioning system primarily at start up in hot, humid climates. The following conditions may cause the odor

1. Debris is present in the HVAC module.
2. Microbial growth on the evaporator core

When the blower motor fan is turned on, the microbial growth may release an unpleasant musty odor into the passenger compartment. To remove odors of this type, the microbial growth must be eliminated. Perform the following procedure

Deodorize the evaporator core using Deodorizing Aerosol Kit.

Perform the following steps in order to deodorize the A/C system

1. Ensure that the plenum which draws outside air into the HVAC module is clear of debris.
2. Disable the A/C compressor clutch operation by disconnecting the clutch coil electrical connector.
3. Dry the evaporator core by performing the following steps: Start the engine. Select the warmest temperature setting. Select the recirculation mode. Run the blower motor on high for 10 minutes.
4. Locate an area in the air conditioning duct between the blower motor and the evaporator core downstream of the blower motor.
5. Drill a 3.175 mm (0.125 in) hole where the hole will not interfere with or damage the following components: The blower motor The evaporator core Any other operating part the of system
6. Wear safety goggles and latex gloves in order to perform the following actions: Select the maximum blower speed. Insert the deodorizer extension tube into the hole to the mark on the extension tube. Use short spray bursts and vary the direction of spray for a 2-3 minute period of time.
7. Shut the engine OFF. Allow the vehicle to sit for 3-5 minutes.
8. Seal the 3.175 mm (0.125 in) hole with body sealer or RTV gasket compound.
9. Start the engine.
10. Operate the blower motor on high for 15-20 minutes to dry.
11. Reconnect the A/C compressor clutch coil electrical connector.
12. Verify proper clutch operation.

1. J 43600 ACR 2000 Air Conditioning Service Center
2. J 45037 A/C Oil Injector

Note. R-134a is the only approved refrigerant for use in this vehicle. The use of any other refrigerant may result in poor system performance or component failure.

Note. To avoid system damage use only R-134a dedicated tools when servicing the A/C system.

Note. Use only Polyalkylene Glycol Synthetic Refrigerant Oil (PAG) for internal circulation through the R-134a A/C system and only 525 viscosity mineral oil on fitting threads and O-rings. If lubricants other than those specified are used, compressor failure and/or fitting seizure may result.

Note. R-12 refrigerant and R-134a refrigerant must never be mixed, even in the smallest of amounts, as they are incompatible with each other. If the refrigerants are mixed, compressor failure is likely to occur. Refer to the manufacturer instructions included with the service equipment before servicing. The J 43600 is a complete air conditioning service center for R-134a. The ACR 2000 recovers, recycles, evacuates and recharges A/C refrigerant quickly, accurately and automatically. The unit has a display screen that contains the function controls and displays prompts that will lead the technician through the recover, recycle, evacuate and recharge operations. R-134a is recovered into and charged out of an internal storage vessel. The ACR 2000 automatically replenishes this vessel from an external source tank in order to maintain a constant 5.45-6.82 kg (12-15 lbs.) of A/C refrigerant. The ACR 2000 has a built in A/C refrigerant identifier that will test for contamination, prior to recovery and will notify the technician if there are foreign gases present in the A/C system. If foreign gases are present, the ACR 2000 will not recover the refrigerant from the A/C system. The ACR 2000 also features automatic air purge, single pass recycling and an automatic oil drain. Refer to the J 43600 ACR 2000 manual for operation and setup instruction. Always recharge the A/C System with the proper amount of R-134a. Refer to Refrigerant System Capacities, See Refrigerant System Capacities for the correct amount.

A/C Refrigerant System Oil Charge Replenishing

If oil was removed from the A/C system during the recovery process or due to component replacement, the oil must be replenished. Oil can be injected into a charged system using J 45037 . For the proper quantities of oil to add to the A/C refrigerant system, Refer to Refrigerant System Capacities, See Refrigerant System Capacities .

1. J 43600 ACR 2000 Air Conditioning Service Center
2. J 45268 Flush Adapter Kit
3. J 41447 Leak Detection Dye
4. J 41459 Leak Detection Dye Injector
5. J 42220 Universal 12V Leak Detection Lamp

Important: Flushing with the ACR 2000 is not intended to remove metal from the A/C system.

Flushing is intended to remove the following contaminants

1. Contaminated PAG oil
2. Desiccant, following a desiccant bag failure
3. Overcharge of PAG oil
4. Refrigerant contamination

Important: Warmer engine or ambient temperature decreases the refrigerant recovery time during the A/C flush procedure.

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1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the orifice tube. Refer to «EXPANSION (ORIFICE) TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
3. Connect the A/C lines with the orifice tube removed.
4. Remove the A/C compressor. Refer to «COMPRESSOR REPLACEMENT (LR4, LM7, AND LQ4)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «COMPRESSOR REPLACEMENT (L18)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Inspect the end of the suction hose for a suction screen.
6. Remove the suction screen, if installed.
7. Install J 45268-4 to the A/C compressor suction hose.
8. Install J 45268-5 to the A/C compressor discharge hose.
9. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil. Perform the following procedure: Important: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with ACDelco P/N GF 470, before each flush. Connect the J 45268-1 flush filter to the suction port of the J 45268-4 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. Connect the red hose from the J 43600 to the J 45268-5 flush adapter.
10. Reverse flow refrigerant flushing is recommended for desiccant bag failure. Perform the following procedure and replace the accumulator when the flush procedure is complete. Important: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve from the filter. Service the filter with AC P/N GF 470, before each flush. Connect the J 45268-1 flush filter to the discharge port of the J 45268-5 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. Connect the red hose from the J 43600 to the suction port of the J 45268-4 flush adapter. Important: Close the valve on the external refrigerant tank, before starting the flush process.
11. Flush the front A/C system. Follow the instructions supplied with the J 43600 . Important: Flush the front A/C system before flushing the auxiliary A/C system.
12. If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately.
13. Cut the orifice tube frame and screen, enough to access the end of the orifice tube. Pinch off the orifice tube. Important: Pinch off the orifice tube in order to prevent refrigerant flow to the front system during the auxiliary system flush.
14. Install the pinched orifice tube. Refer to «EXPANSION (ORIFICE) TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
15. Remove the auxiliary TXV. Refer to «THERMAL EXPANSION VALVE REPLACEMENT - AUXILIARY»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
16. Install the J 45268-104. Important: The auxiliary evaporator core can be flushed without totally reassembling into the auxiliary HVAC module.
17. Install the auxiliary evaporator core to the A/C lines.
18. Raise the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) General Information.
19. Connect the auxiliary A/C lines to the auxiliary evaporator core.
20. Lower the vehicle.
21. Flush the auxiliary A/C system. Follow the instructions supplied with the J 43600 .
22. Raise the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
23. Remove the auxiliary A/C lines from the auxiliary evaporator core.
24. Lower the vehicle.
25. Remove the J 45268-104.
26. Inspect the TXV for debris. Clean or replace as needed.
27. Install the auxiliary TXV. Refer to «THERMAL EXPANSION VALVE REPLACEMENT - AUXILIARY»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
28. Remove the J 45268-4 from the A/C compressor suction hose.
29. Remove the J 45268-5 from the A/C compressor discharge hose. Important: Flushing will remove all the PAG oil from the A/C system. The A/C system must be replenished with the correct amount of PAG oil.
30. If the removed A/C compressor is being reinstalled, perform the following procedure: Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the A/C compressor. Add the total system capacity of PAG oil to the A/C compressor.
31. If you will replace the A/C compressor after flushing the system, perform the following procedure: Determine if the new service compressor is shipped with PAG oil. Refer to the. If the service compressor is shipped with PAG oil, DO NOT drain the new PAG oil from the compressor. Deduct the amount of PAG oil shipped with the service compressor from the amount of PAG oil listed in the capacities table. Add the calculated amount to the compressor, as needed.
32. Install the A/C compressor. Refer to «COMPRESSOR REPLACEMENT (LR4, LM7, AND LQ4)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «COMPRESSOR REPLACEMENT (L18)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
33. Install a new orifice tube. Refer to «EXPANSION (ORIFICE) TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
34. Evacuate and recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) . Important: Flushing will remove the fluorescent leak detection dye from the A/C system.
35. Add one bottle of J 41447 using the J 41459 .
36. Leak test the fittings using J 42220 .

Draining

Important: Drain and measure as much of the refrigerant oil as possible from the removed compressor.

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1. Drain the oil from both the suction and discharge ports of the removed compressor into a clean, graduated container. Rotate the compressor shaft to assist in draining the compressor.
2. Measure and record the amount of oil drained from the removed compressor. This measurement will be used during installation of the replacement compressor.
3. Properly discard the used refrigerant oil.

Balancing

Important: The refrigerant oil in the A/C system must be balanced during compressor replacement.

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1. The replacement compressor is shipped with the total system capacity of refrigerant oil.
2. Before installing the compressor, the refrigerant oil will have to be partially drained: Refer to the amount of refrigerant oil recorded during the compressor removal. Subtract the amount recorded from the total system capacity. Refer to Refrigerant System Capacities, See «Refrigerant System Capacities»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) . The difference between the total system capacity and the recorded amount is the calculated amount to be drained from the replacement compressor.
3. Drain the calculated amount of refrigerant oil from the replacement compressor.

J 39400-A Halogen Leak Detector

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1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Install a ratchet into the air conditioning (A/C) belt tensioner adapter opening.
3. Rotate the A/C belt tensioner clockwise in order to relieve the tension on the belt.
4. Remove the A/C belt from the A/C compressor.
5. Slowly release the tension on the A/C belt tensioner.
6. Remove the right front tire and wheel assembly. Refer to TIRE AND WHEEL REMOVAL AND INSTALLATION in Tires and Wheels.
7. Remove the wheel house panel from the vehicle. Refer to WHEELHOUSE PANEL REPLACEMENT in Body Front End.
8. Remove the discharge hose bolt from the A/C compressor.
9. Remove the discharge hose from the A/C compressor.
10. Remove the suction hose bolt from the A/C compressor.
11. Remove the suction hose from the A/C compressor.
12. Discard the sealing washers. Cap all of the openings.
13. Disconnect the electrical connections.
14. Remove the A/C compressor mounting bolts. The lower right bolt (3) will stay with the compressor due to a lack of clearance.
15. Remove the A/C compressor (2) from the bracket (1).
16. If replacing the A/C compressor. Refer to «COMPRESSOR OIL BALANCING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

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1. Install the A/C compressor (2) to the bracket (1) through the fender well. Insert the mounting bolt (3) into the lower right mounting boss before installing the A/C compressor.
2. Install the A/C compressor to the bracket. Insert the mounting bolt into the lower right mount before installing the A/C compressor. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the A/C compressor mounting bolts. Tighten Tighten the bolts to 50 N.m (37 lb ft).
4. Connect the electrical connector to the A/C compressor.
5. Install the A/C discharge hose to the compressor using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
6. Install the A/C discharge hose bolt to the A/C compressor. Tighten Tighten the bolt to 16 N.m (12 lb ft).
7. Install the A/C suction hose to the compressor using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
8. Install the A/C suction hose bolt to the A/C compressor. Tighten Tighten the bolt to 16 N.m (12 lb ft).
9. Install the wheel house panel to the vehicle. Refer to WHEELHOUSE PANEL REPLACEMENT in Body Front End.
10. Install the right front tire and wheel assembly. Refer to TIRE AND WHEEL REMOVAL AND INSTALLATION in Tires and Wheels.
11. Install the A/C drive belt. Refer to «DRIVE BELT REPLACEMENT -- AIR CONDITIONING»(/chevrolet/avalanche/i-2001-2006/remont/mechanical/#engine-mechanical-48l-53l-60l) in Engine Mechanical - 4.8L, 5.3L, and 6.0L.
12. Evacuate and recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
13. Leak test the fittings of the component using the J 39400-A .

J 39400-A Halogen Leak Detector

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1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the intake air resonator replacement.
3. Install a ratchet into the air conditioning (A/C) belt tensioner adapter opening.
4. Rotate the A/C belt tensioner clockwise in order to relieve the tension on the belt.
5. Remove the A/C belt from the A/C compressor.
6. Slowly release the tension on the A/C belt tensioner.
7. Remove the discharge hose bolt from the A/C compressor.
8. Remove the discharge hose from the A/C compressor.
9. Remove the suction hose bolt from the A/C compressor.
10. Remove the suction hose from the A/C compressor.
11. Discard the sealing washers. Cap all of the openings.
12. Disconnect the electrical connections.
13. Remove the A/C compressor mounting bolts.
14. Remove the A/C compressor (2) from the bracket (1).
15. If replacing the A/C compressor. Refer to «COMPRESSOR OIL BALANCING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

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1. Install the A/C compressor (2) to the A/C bracket (1). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the A/C compressor mounting bolts. Tighten Tighten the bolts to 50 N.m (37 lb ft).
3. Connect the electrical connector to the A/C compressor.
4. Install the A/C discharge hose to the compressor using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Install the A/C discharge hose bolt to the A/C compressor. Tighten Tighten the bolt to 16 N.m (12 lb ft).
6. Install the A/C suction hose to the compressor using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
7. Install the A/C suction hose bolt to the A/C compressor. Tighten Tighten the bolt to 16 N.m (12 lb ft).
8. Install the intake air resonator replacement.
9. Install the A/C drive belt. Refer to «DRIVE BELT REPLACEMENT -- AIR CONDITIONING»(/chevrolet/avalanche/i-2001-2006/remont/mechanical/#engine-mechanical-48l-53l-60l) in Engine Mechanical - 4.8L, 5.3L, and 6.0L.
10. Evacuate and recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
11. Leak test the fittings of the component using the J 39400-A .

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1. Raise and suitably support the vehicle. Refer to in General Information.
2. Remove the engine protection shield.
3. Install a ratchet into the air conditioning (A/C) belt tensioner adapter opening.
4. Rotate the A/C belt tensioner clockwise in order to relieve the tension on the belt.
5. Remove the A/C belt from the A/C compressor.
6. Slowly release the tension on the A/C belt tensioner.
7. Remove the clutch plate retaining bolt (1).
8. Remove the clutch plate assembly (2).
9. Remove the clutch hub/bearing snap ring (3).
10. Remove the clutch hub/bearing assembly (4).

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1. Install the clutch hub/bearing assembly (4).
2. Install the clutch hub/bearing snap ring (3).
3. Install the clutch plate assembly (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the clutch plate retaining bolt (1). Tighten Tighten the bolt to 18 N.m (13 lb ft).
5. Install a ratchet into the A/C belt tensioner adapter opening.
6. Rotate the A/C belt tensioner clockwise in order to relieve the tension on the belt.
7. Install the A/C belt to the A/C compressor.
8. Slowly release the tension on the A/C belt tensioner.
9. Remove the ratchet from the A/C belt tensioner.
10. Install the engine protection shield.
11. Lower the vehicle.

Scheme 47

1. Remove the A/C compressor. Refer to «COMPRESSOR REPLACEMENT (LR4, LM7, AND LQ4)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «COMPRESSOR REPLACEMENT (L18)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the A/C belt tensioner bolts.
3. Remove the A/C belt tensioner.
4. Remove the A/C compressor bracket mounting bolts.
5. Remove the A/C compressor bracket.

Scheme 48

1. Install the A/C compressor bracket. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the A/C compressor bracket mounting bolts. Tighten Tighten the bolts to 50 N.m (37 lb ft).
3. Install the A/C belt tensioner.
4. Install the A/C belt tensioner bolts. Tighten Tighten the bolts to 50 N.m (37 lb ft).
5. Install the A/C compressor. Refer to «COMPRESSOR REPLACEMENT (LR4, LM7, AND LQ4)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «COMPRESSOR REPLACEMENT (L18)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 49

1. Remove the seal washer from the A/C refrigerant component. Important: Cap or tape the open A/C refrigerant components immediately to prevent system contamination.
2. Inspect the seal washer for signs of damage to help determine the root cause of the failure.
3. Inspect the A/C refrigerant components for damage or burrs. Repair if necessary. Important: DO NOT reuse sealing washer.
4. Discard the sealing washer.

Installation Procedure

Important: Flat washer type seals do not require lubrication.

Scheme 50

1. Inspect the new seal washer for any signs of cracks, cuts, or damage. Do not use a damaged seal washer.
2. Remove the cap or tape from the A/C refrigerant components.
3. Using a lint-free clean, dry cloth, clean the sealing surfaces of the A/C refrigerant components.
4. Carefully install the new seal washer onto the A/C refrigerant component. The washer must completely bottom against the surface of the fitting. Important: After tightening the A/C components, there should be a slight sealing washer gap of approximately 1.2 mm (3/64 in) between the A/C line and the A/C component.
5. Assemble the remaining A/C refrigerant components. Refer to the appropriate repair procedure.

Scheme 51

1. Disassemble the A/C refrigerant components. Refer to the appropriate repair procedure For compression style fittings use a back up wrench on the fitting (2) and loosen the fitting nut (1). For banjo style fittings remove the bolt retaining the banjo type fitting.
2. Remove the O-ring seal from the A/C refrigerant component.
3. Inspect the O-ring seal for signs of damage to help determine the root cause of the failure.
4. Inspect the A/C refrigerant components for damage or burrs. Repair if necessary. Important: Cap or tape the open A/C refrigerant components immediately to prevent system contamination.
5. Cap or tape the A/C refrigerant components.
6. Discard the O-ring seal.

Scheme 52

Scheme 53

1. Inspect the new O-ring seal for any sign or cracks, cuts, or damage. Replace if necessary.
2. Remove the cap or tape from the A/C refrigerant components.
3. Using a lint-free clean, dry cloth, carefully clean the sealing surfaces of the A/C refrigerant components. Important: DO NOT allow any of the mineral base 525 viscosity refrigerant oil on the new O-ring seal to enter the refrigerant system.
4. Lightly coat the new O-ring seal with mineral base 525 viscosity refrigerant oil. Important: DO NOT reuse O-ring seals.
5. Carefully slide the new O-ring seal onto the A/C refrigerant component.
6. The O-ring seal must be fully seated.
7. Assemble the A/C components. Refer to the appropriate repair procedure. For compression style fittings use a back up wrench on the fitting (2) and tighten the fitting nut (1) to specification. For banjo style fittings install the bolt retaining the banjo type fitting and tighten to specification.

J 39400-A Halogen Leak Detector

Scheme 54

Scheme 55

1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the discharge hose mounting bolt (2) from the A/C compressor.
3. Remove the discharge hose (1) from the A/C compressor.
4. Remove the upper radiator baffle. Refer to RADIATOR AIR BAFFLE AND DEFLECTOR REPLACEMENT - UPPER in Engine Cooling.
5. Remove the discharge hose nut from the condenser.
6. Remove the discharge hose from the condenser.
7. Disconnect the electrical connector from the A/C recirculation switch.
8. Remove the discharge hose from the vehicle.
9. Discard all of the used sealing washers. Cap the system openings.

Scheme 56

Scheme 57

Scheme 58

1. Install the discharge hose (1) to the vehicle.
2. Connect the electrical connector to the A/C recirculation switch.
3. Install the discharge hose to the condenser using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) . NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the discharge hose nut to the condenser. Tighten Tighten the nut to 16 N.m (12 lb ft).
5. Install the upper air baffle. Refer to RADIATOR AIR BAFFLE AND DEFLECTOR REPLACEMENT - UPPER in Engine Cooling.
6. Install the discharge hose (1) to the A/C compressor using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
7. Install the discharge hose mounting bolt. Tighten Tighten the bolt to 16 N.m (12 lb ft).
8. Evacuate and recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
9. Leak test the fittings of the component using the J 39400-A.

J 39400-A Halogen Leak Detector

Scheme 59

Scheme 60

1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the suction hose mounting bolt from the A/C compressor.
3. Remove the suction hose (2) from the A/C compressor.
4. Remove the suction hose nut from the accumulator.
5. Remove the suction hose from the accumulator.
6. Remove the suction hose assembly from the vehicle.
7. Discard all of the used sealing washers. Cap the system openings.

Scheme 61

Scheme 62

1. Install the suction hose to the vehicle.
2. Install the suction hose to the accumulator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the suction hose nut to the accumulator. Tighten Tighten the nut to 16 N.m (12 lb ft).
4. Install the suction hose (2) to the compressor using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Install the suction hose mounting bolt to the A/C compressor. Tighten Tighten the bolt to 16 N.m (12 lb ft).
6. Evacuate and recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
7. Leak test the fittings of the component using the J 39400-A .

J 39400-A Halogen Leak Detector

Scheme 63

Scheme 64

1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the evaporator tube nut from the evaporator.
3. Disconnect the evaporator tube from the evaporator.
4. Remove the evaporator tube nut from the auxiliary A/C tube, if equipped.
5. Disconnect the evaporator tube from the auxiliary A/C tube, if equipped.
6. Remove the right park/turn signal lamp. Refer to PARK/TURN SIGNAL LAMP REPLACEMENT (EXCEPT AVALANCHE) or PARK/TURN SIGNAL LAMP REPLACEMENT (AVALANCHE) in Lighting Systems.
7. Remove the grille from the vehicle. Refer to GRILLE REPLACEMENT (CADILLAC) or GRILLE REPLACEMENT (AVALANCHE) in Exterior Trim.
8. Remove the evaporator tube nut from the condenser.
9. Disconnect the evaporator tube from the condenser.
10. Remove the evaporator tube from the vehicle.
11. Discard all of the used sealing washers. Cap all of the open connections.

Scheme 65

Scheme 66

1. Connect the evaporator tube to the condenser using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) . NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the evaporator tube nut to the condenser. Tighten Tighten the nut to 16 N.m (12 lb ft).
3. Install the grille to the vehicle. Refer to GRILLE REPLACEMENT (CADILLAC) or GRILLE REPLACEMENT (AVALANCHE) in Exterior Trim.
4. Install the right park/turn signal lamp. Refer to PARK/TURN SIGNAL LAMP REPLACEMENT (EXCEPT AVALANCHE) or PARK/TURN SIGNAL LAMP REPLACEMENT (AVALANCHE) in Lighting Systems.
5. Connect the evaporator tube to the auxiliary A/C tube using new sealing washers, if equipped. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
6. Install the evaporator tube nut to the auxiliary A/C tube, if equipped. Tighten Tighten the nut to 16 N.m (12 lb ft).
7. Install the evaporator tube to the evaporator.
8. Install the evaporator tube nut to the evaporator. Tighten Tighten the nut to 16 N.m (12 lb ft).
9. Evacuate and recharge the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
10. Leak test the fittings of the components using the J 39400-A .

J 39400-A Halogen Leak Detector

Important: The A/C Refrigerant filter, ACDelco P/N 15-1696 must be installed to the A/C evaporator tube between the condenser and evaporator. The installation of this A/C refrigerant filter eliminates the need for flushing.

Scheme 67

Scheme 68

Scheme 69

Scheme 70

1. Remove the air cleaner.
2. Measure 50 mm (2 in) from the bend on the evaporator tube (2) near the expansion tube end and mark the location.
3. Measure 50.8 mm (2 in) from the mark on the evaporator tube (2) from the previous step. Important: Do not allow metal burrs to enter the evaporator tube (2) during cutting or when removing the burrs.
4. Using a tubing cutter, cut the marked section of the evaporator tube (2).
5. Remove the burrs from the evaporator tube (2).
6. Remove the nuts (4), the ferrules (3), and the O-rings (2) from the A/C refrigerant filter (1). Important: DO NOT install the O-rings (2) in this step.
7. Push the nuts (4) and ferrules (3) over each of the evaporator tube halves.
8. Install the ferrules (3) with the small end toward the nut (4).
9. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards the evaporator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
10. While holding the evaporator tube in the A/C refrigerant filter (1), tighten the nuts (4) to the A/C refrigerant filter (1). Tighten Tighten the nuts to 15 N.m (11 lb ft).
11. Remove the nuts (4) from the A/C refrigerant filter (1).
12. Install the O-rings (2) to the evaporator tube halves. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
13. Install the nuts (4) to the A/C refrigerant filter (1). Tighten Tighten the nuts to 15 N.m (11 lb ft).
14. Evacuate and recharge the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
15. Leak test the fittings of the component using the J 39400-A .
16. Install the air cleaner.

J 39400-A Halogen Leak Detector

Important: The A/C refrigerant filter, ACDelco P/N 15-1696 must be installed to the A/C evaporator tube (liquid line) between the condenser and evaporator. The installation of this A/C refrigerant filter eliminates the need for flushing.

Scheme 71

Scheme 72

Scheme 73

Scheme 74

Scheme 75

1. Remove the air cleaner.
2. Remove the evaporator tube (2) from the vehicle. Refer to «EVAPORATOR TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
3. Measure 45 mm (1.75 in) from the bend on the condenser end of the evaporator tube (2) and mark the location.
4. Measure 50.8 mm (2 in) from the mark on the evaporator tube (2) towards the evaporator from the previous step. Important: Do not allow metal burrs to enter the evaporator tube (2) during cutting or when removing the burrs.
5. Using a tubing cutter, cut the marked section of the evaporator tube (2).
6. Remove the burrs from the evaporator tube (2).
7. Remove the nuts (4), the ferrules (3), and the O-rings (2) from the A/C refrigerant filter (1). Important: Do Not install the O-rings (2) in this step.
8. Push the nuts (4) and ferrules (3) over each of the evaporator tube halves.
9. Install the ferrules (3) with the small end toward the nut (4).
10. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards the evaporator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
11. While holding the evaporator tube in the A/C refrigerant filter (1), tighten the nuts (4) to the A/C refrigerant filter (1). Tighten Tighten the nuts to 15 N.m (11 lb ft).
12. Remove the nuts (4) from the A/C refrigerant filter (1).
13. Install the O-rings (2) to the evaporator tube halves. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
14. Install the nuts (4) to the A/C refrigerant filter (1). Tighten Tighten the nuts to 15 N.m (11 lb ft).
15. Install the evaporator tube (2) to the vehicle. Refer to «EVAPORATOR TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
16. Evacuate and recharge the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
17. Leak test the fittings of the component using the J 39400-A .
18. Install the air cleaner.

J 39400-A Halogen Leak Detector

Scheme 76

Scheme 77

1. Recover the refrigerant from the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the air cleaner. Important: The nuts (4) and the ferrules (3) will remain on the evaporator tube. Do not try to remove.
3. Remove the nuts (4) from the A/C refrigerant filter (1).
4. Remove the A/C refrigerant filter (3) from the evaporator tube (2).

Scheme 78

Scheme 79

Scheme 80

1. Install the O-rings (2) to the evaporator tube. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards the evaporator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the nuts (4) to the A/C refrigerant filter (1) Tighten Tighten the nuts to 15 N.m (11 lb ft).
4. Recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Leak test the fittings of the component using the J 39400-A .
6. Install the air cleaner.

J 39400-A Halogen Leak Detector

Scheme 81

Scheme 82

Scheme 83

1. Recover the refrigerant from the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the air cleaner.
3. Remove the evaporator tube (2) from the vehicle. Refer to «EVAPORATOR TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) . Important: The nuts (4) and ferrules (3) will remain on the evaporator tube. Do not try to remove.
4. Remove the nuts (4) from the A/C refrigerant filter (1).
5. Remove the A/C refrigerant filter (3) from the evaporator tube (2).

Scheme 84

Scheme 85

Scheme 86

Scheme 87

1. Install the O-rings (2) to the evaporator tube. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards the evaporator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the nuts (4) to the A/C refrigerant filter (1). Tighten Tighten the nuts to 15 N.m (11 lb ft).
4. Install the evaporator tube (2) to the vehicle. Refer to «EVAPORATOR TUBE REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Recharge the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
6. Leak test the fittings of the component using the J 39400-A .
7. Install the air cleaner.

1. J 26549-E Orifice Tube Remover
2. J 39400-A Halogen Leak Detector

Scheme 88

1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Loosen the nut from the evaporator tube fitting.
3. Use the J 26549-E in order to remove the orifice tube (1) from the evaporator tube (2).
4. Cap or plug the open line.

Scheme 89

1. Uncap or unplug the evaporator tube.
2. Install the new O-ring seal. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
3. Install the short screen end of the new orifice (1) into the evaporator tube. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Connect the evaporator tube at the fitting. Tighten Tighten the fitting to 25 N.m (18 lb ft).
5. Evacuate and recharge the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
6. Leak test the fittings of the repaired component using J 39400-A .

Scheme 90

1. Remove the cover from the underhood convenience center (1).
2. Remove the compressor relay (2).

Scheme 91

1. Install the compressor relay (2).
2. Install the cover to the underhood convenience center (1).

Scheme 92

1. Disconnect the electrical connector from the A/C low pressure switch.
2. Remove the A/C low pressure switch from the accumulator.
3. Remove the O-ring and discard.

Scheme 93

1. Install the new O-ring seal to the switch. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the A/C low pressure switch to the accumulator. Tighten Tighten the switch to 6 N.m (53 lb in).
3. Connect the electrical connector to the A/C low pressure switch.
4. Leak test the fittings of the components using the J 39400-A .

Scheme 94

1. Raise and support the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
2. Disconnect the electrical connector from the A/C high pressure recirculation switch.
3. Remove the A/C high pressure recirculation switch from the evaporator tube.

Note. Refer to FASTENER NOTICE in Cautions and Notices.

Scheme 95

1. Install the A/C high pressure recirculation switch. Tighten Tighten the switch to 6 N.m (53 lb in).
2. Connect the electrical connector to the A/C high pressure recirculation switch.
3. Leak test the fittings of the components using the J 39400-A .
4. Lower the vehicle.

J 39400-A Halogen Leak Detector

Scheme 96

Scheme 97

Scheme 98

Scheme 99

Scheme 100

1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the grille. Refer to GRILLE REPLACEMENT (CADILLAC) or GRILLE REPLACEMENT (AVALANCHE) in Exterior Trim.
3. Remove the tie bar to radiator brace bolts (1). Access the bolts from the rear of the upper radiator support.
4. Remove the lower bolts from the hood latch support bracket.
5. Remove the compressor discharge hose assembly bolt from the condenser.
6. Disconnect the compressor discharge hose assembly from the condenser.
7. Remove the evaporator tube nut from the condenser.
8. Disconnect the evaporator tube from the condenser.
9. Remove the insulator retainer bolts and the upper insulator retainers.
10. Remove the condenser from the vehicle.

Important: If replacing the condenser, add the refrigerant oil to the condenser. Refer to Refrigerant System Capacities, See Refrigerant System Capacities for system capacity information.

Scheme 101

Scheme 102

Scheme 103

Scheme 104

Scheme 105

1. Install the condenser to the vehicle. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the upper insulator retainers and the insulator retainer bolts. Tighten Tighten the bolts to 2.4 N.m (21 lb in).
3. Connect the evaporator tube to the condenser using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
4. Install the evaporator tube nut to the condenser. Tighten Tighten the nut to 16 N.m (12 lb ft).
5. Connect the compressor discharge hose to the condenser using new sealing washers. Refer to «SEALING WASHER REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning)
6. Install the compressor discharge hose nut to the condenser. Tighten Tighten the nut to 16 N.m (12 lb ft).
7. Install the lower bolts to the hood latch support bracket. Tighten Tighten the bolts to 9 N.m (80 lb in).
8. Install the tie bar to radiator brace bolts (1). Access the bolts from the rear of the upper radiator support. Tighten Tighten the bolts to 9 N.m (80 lb in).
9. Install the grille. Refer to GRILLE REPLACEMENT (CADILLAC) or GRILLE REPLACEMENT (AVALANCHE) in Exterior Trim.
10. Evacuate and recharge the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
11. Leak test the fittings of the component using the J 39400-A .

J 39400-A Halogen Leak Detector

Scheme 106

Scheme 107

Scheme 108

1. Recover the refrigerant. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the evaporator tube nut from the evaporator.
3. Remove the evaporator tube from the evaporator.
4. Remove the nut from the evaporator tube (3).
5. Disconnect the electrical connector from the A/C low pressure switch.
6. Remove the compressor hose nut from the accumulator.
7. Remove the compressor hose from the accumulator.
8. Remove the nut (2) from the evaporator fitting.
9. Remove the accumulator bracket nut (4) from the retaining stud.
10. Remove the accumulator (3).
11. Remove the retaining bracket bolt (5).
12. Remove the retaining bracket (6) from the accumulator.
13. Remove and discard the O-ring seals.

Scheme 109

Important: If replacing the accumulator, add the refrigerant oil to the condenser. Refer to Refrigerant System Capacities, See Refrigerant System Capacities for system capacity information.

Scheme 110

Scheme 111

1. Install the O-ring seals. Refer to «O-RING REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Install the retaining bracket (6) to the accumulator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the retaining bracket bolt (5). Tighten Tighten the bolt to 10 N.m (89 lb in).
4. Install the accumulator (3).
5. Install the accumulator bracket nut (4). Tighten Tighten the nut to 9 N.m (80 lb in).
6. Install the nut (2) to the evaporator fitting. Tighten Tighten the nut to 16 N.m (12 lb ft).
7. Install the compressor hose to the accumulator.
8. Install the compressor hose nut to the accumulator. Tighten Tighten the nut to 16 N.m (12 lb ft).
9. Connect the electrical connector to the A/C low pressure switch.
10. Install the nut to the evaporator tube (3). Tighten Tighten the nut to 25 N.m (18 lb ft).
11. Install the evaporator tube to the evaporator.
12. Install the evaporator tube nut to the evaporator. Tighten Tighten the nut to 16 N.m (12 lb ft).
13. Evacuate and recharge the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
14. Leak test the fittings of the component using the J 39400-A .

J 43181 Quick Connect Connector Removal Tool

Scheme 112

Scheme 113

1. Drain the engine coolant. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Using the J 43181 disconnect the inlet heater hose from the heater core. Install the J 43181 to the heater core pipe. Close the tool around the heater core pipe. Firmly pull the tool into the quick connect end of the heater hose. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the inlet hose from the heater core.
3. Using the J 43181 disconnect the surge tank outlet hose from the heater core. Install the J 43181 to the heater core pipe. Close the tool around the heater core pipe. Firmly pull the tool into the quick connect end of the heater hose. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the surge tank outlet hose from the heater core.
4. Remove the accumulator. Refer to «ACCUMULATOR REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Remove the instrument panel carrier. Refer to INSTRUMENT PANEL (I/P) CARRIER REPLACEMENT in Instrument Panel, Gages and Console.
6. Remove the HVAC module drain hose.
7. Disconnect the electrical harnesses and the ground connections from the HVAC module.
8. Remove the nuts (4) from the HVAC module (2).
9. Remove the bolts (3) from the HVAC module (2).
10. Remove the HVAC module (2) from the vehicle (1).

Scheme 114

Scheme 115

1. If replacing the HVAC module, transfer the components from the old HVAC module as necessary.
2. Install the HVAC module (2) to the vehicle (1). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the nuts (4) to the HVAC module (2). Tighten Tighten the nuts to 9 N.m (80 lb in).
4. Install the bolts(4) to the HVAC module (2). Tighten Tighten the bolts to 4 N.m (35 lb in).
5. Connect the electrical harnesses and the ground connections.
6. Install the HVAC module drain hose.
7. Install the instrument panel carrier. Refer to INSTRUMENT PANEL (I/P) CARRIER REPLACEMENT in Instrument Panel, Gages and Console.
8. Install the accumulator. Refer to «ACCUMULATOR REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
9. Install the surge tank outlet hose to the heater core. Firmly push the quick connect onto the heater core pipe until you hear an audible click.
10. Install the inlet heater hose to the heater core. Firmly push the quick connect onto the heater core pipe until you hear an audible click.
11. Fill the engine coolant. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

Scheme 116

Scheme 117

Scheme 118

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the electrical connector from the recirculation actuator.
3. Remove the screws from the evaporator cover (1).
4. Remove the evaporator cover (1) from the HVAC module assembly (2).
5. Remove the evaporator cowl gasket (1) from the evaporator (2).
6. Remove the evaporator core (1) from the HVAC module assembly (2).

Important: If replacing the condenser, add the refrigerant oil to the evaporator core. Refer to Refrigerant System Capacities, See Refrigerant System Capacities .

Scheme 119

Scheme 120

Scheme 121

1. Install the evaporator core (1) to the HVAC module assembly (2).
2. Install the evaporator cowl gasket (1) to the evaporator (2).
3. Install the evaporator cover (1) to the HVAC module assembly (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the evaporator cover (1). Tighten Tighten the screws to 2 N.m (18 lb in).
5. Connect the electrical connector to the recirculation actuator (1).
6. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 122

Scheme 123

Scheme 124

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. If equipped remove the heat stakes (1) from the HVAC module (2) with a screw driver and a hammer.
3. If equipped remove the screws from the HVAC module assembly.
4. Remove the evaporator cowl gasket from the evaporator.
5. Separate the upper HVAC module assembly (2) from the lower HVAC module assembly (1)
6. Remove the evaporator core (1) from the upper HVAC module assembly (2).

Important: If replacing the evaporator core, add the refrigerant oil to the evaporator core. Refer to Refrigerant System Capacities, See Refrigerant System Capacities .

Scheme 125

Scheme 126

1. Install the evaporator core (1) to the HVAC module assembly (2).
2. Install the upper HVAC module assembly (2) from the lower HVAC module assembly (1)
3. Install the evaporator cowl gasket to the evaporator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the HVAC module assembly. Tighten Tighten the screws to 2 N.m (18 lb in).
5. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 127

Scheme 128

Scheme 129

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hoses from the mounting clip.
4. Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
6. Remove the inlet heater hose (1) from the coolant outlet fitting.
7. Remove the inlet heater hose.

Scheme 130

Scheme 131

1. Install the inlet heater hose.
2. Install the inlet heater hose (1) to the coolant outlet fitting.
3. Connect the heater and surge tank hoses to the heater core. Important: Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Install the heater and surge tank hoses to the mounting clip.
5. Install the air intake tube.
6. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

Scheme 132

Scheme 133

Scheme 134

Scheme 135

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hoses from the mounting clip.
4. Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
6. Remove the inlet heater hose from the water pump.
7. Remove the inlet heater hose.

Scheme 136

Scheme 137

Scheme 138

1. Install the inlet heater hose.
2. Install the inlet heater hose to the water pump.
3. Connect the heater hose to the heater core. Important: Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Install the heater and surge tank hoses to the mounting clip.
5. Install the air intake tube.
6. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

J 43181 Quick Connect Connector Removal Tool

Scheme 139

Scheme 140

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hose from the mounting clip.
4. Using the J 43181 disconnect the heater hose from the heater core inlet. Install the J 43181 to the heater core pipe. Close the tool around the heater core pipe. Firmly pull the tool into the quick connect end of the heater hose. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.
5. Remove the inlet heater hose (1) from the engine coolant inlet fitting.
6. Remove the inlet heater hose.

Scheme 141

Scheme 142

1. Install the inlet heater hose.
2. Install the inlet heater hose (1) to the engine coolant inlet fitting.
3. Connect the heater and surge tank hose to the heater core. Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Install the heater and surge tank hose to the mounting clip.
5. Install the air intake tube.
6. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

J 43181 Quick Connect Connector Removal Tool

Scheme 143

Scheme 144

Scheme 145

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hose from the mounting clip.
4. Using the J 43181 disconnect the heater hose from the heater core inlet. Install the J 43181 to the heater core pipe. Close the tool around the heater core pipe. Firmly pull the tool into the quick connect end of the heater hose. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.
5. Remove the inlet heater hose from the engine.
6. Remove the inlet heater hose.

Scheme 146

Scheme 147

1. Install the inlet heater hose.
2. Install the inlet heater hose to the engine.
3. Connect the heater and surge tank hose to the heater core. Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Install the heater and surge tank hose to the mounting clip.
5. Install the air intake tube.
6. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

Scheme 148

Scheme 149

Scheme 150

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hoses from the mounting clip.
4. Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
6. Remove the outlet heater hose from the radiator.
7. Remove the outlet heater hose (1).

Scheme 151

Scheme 152

1. Install the outlet heater hose (1).
2. Install the outlet heater hose to the radiator.
3. Connect the heater and surge tank hoses to the heater core. Important: Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Pull the heater outlet hose to ensure the connection.
5. Install the heater and surge tank hoses to the mounting clip.
6. Install the air intake tube.
7. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

Scheme 153

Scheme 154

Scheme 155

Scheme 156

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hoses from the mounting clip.
4. Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
6. Remove the outlet heater hose from the water pump.
7. Reposition the outlet heater hose clamp at the surge tank.
8. Remove the outlet heater hose from the surge tank.
9. Remove the outlet heater hose.

Scheme 157

Scheme 158

Scheme 159

1. Install the outlet heater hose.
2. Install the outlet heater hose to the water pump.
3. Install the outlet heater hose to the surge tank.
4. Install the outlet heater hose clamp to the surge tank.
5. Connect the heater and surge tank hoses to the heater core. Important: Firmly push the quick connect onto the heater core hose until you hear an audible click.
6. Pull the heater outlet hose to ensure the connection.
7. Install the heater and surge tank hoses to the mounting clip.
8. Install the air intake tube.
9. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

J 43181 Quick Connect Connector Removal Tool

Scheme 160

Scheme 161

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hose from the mounting clip.
4. Using the J 43181 disconnect the heater hoses from the heater core outlet. Install the J 43181 to the heater core pipe. Close the tool around the heater core pipe. Firmly pull the tool into the quick connect end of the heater hose. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.
5. Remove the outlet heater hose from the radiator.
6. Remove the outlet heater hose (1).

Scheme 162

Scheme 163

1. Install the outlet heater hose (1).
2. Install the outlet heater hose to the radiator.
3. Connect the heater and surge tank hoses to the heater core. Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Install the heater and surge tank hose to the mounting clip.
5. Install the air intake tube.
6. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

J 43181 Quick Connect Connector Removal Tool

Scheme 164

Scheme 165

Scheme 166

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Remove the air intake tube.
3. Remove the heater and surge tank hose from the mounting clip.
4. Using the J 43181 disconnect the heater hose from the heater core outlet. Install the J 43181 to the heater core pipe. Close the tool around the heater core pipe. Firmly pull the tool into the quick connect end of the heater hose. Firmly grasp the heater hose. Pull the heater hose forward in order to disengage the hose from the heater core.
5. Remove the outlet heater hose from the engine.
6. Remove the outlet heater hose.

Scheme 167

Scheme 168

1. Install the outlet heater hose.
2. Install the outlet heater hose to the engine.
3. Connect the outlet heater hose to the heater core. Firmly push the quick connect onto the heater core pipe until you hear an audible click.
4. Install the heater and surge tank hose to the mounting clip.
5. Install the air intake tube.
6. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

Scheme 169

Scheme 170

Scheme 171

1. If equipped, remove the IP sound insulator. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.
2. Disconnect the electrical connection from the blower motor.
3. Disconnect the electrical connection from the blower motor resistor.
4. Remove the blower motor resistor retaining screws.
5. Remove the blower motor resistor.

Scheme 172

Scheme 173

Scheme 174

1. Install the blower motor resistor. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the blower motor resistor retaining screws. Tighten Tighten the screws to 1.6 N.m (14 lb in).
3. Connect the electrical connection to the blower motor resistor.
4. Connect the electrical connection to the blower motor.
5. If equipped, install the IP sound insulator. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.

Scheme 175

Scheme 176

Scheme 177

1. If equipped, remove the sound insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.
2. Remove the blower motor insulating cover screws.
3. Disconnect the electrical connector from the blower motor.
4. Remove the blower motor insulating cover.
5. Pull the retaining tab down while turning the blower motor counterclockwise in order to disengage the blower motor from the heater/ventilation module.
6. Remove the blower motor.

Scheme 178

Scheme 179

Scheme 180

1. Install the blower motor.
2. Install the blower motor to the heater/ventilation module. Turn the blower assembly clockwise until the retaining tab locks into place.
3. Install the blower motor insulating cover.
4. Connect the electrical connector to the blower motor. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
5. Install the blower motor insulating cover screws. Tighten Tighten the screws to 1.6 N.m (14 lb in).
6. If equipped, install the sound insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.

Scheme 181

1. Remove the sound insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.
2. Disconnect the electrical connector (2) from the blower motor (1)
3. Remove the screws from the blower motor (1).
4. Remove the blower motor (1) from the HVAC module (3).
5. Remove the retainer from the blower motor wheel. Discard the retainer.
6. Remove the blower motor wheel from the blower motor (1).

Scheme 182

1. Install the blower motor wheel to the blower motor (1).
2. Install the New retainer to the blower motor wheel.
3. Install the blower motor (1) to the HVAC module (3). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the blower motor (1). Tighten Tighten the screws to 2 N.m (18 lb in).
5. Connect the electrical connector (2) to the blower motor (1).
6. Install the sound insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.

Scheme 183

1. Remove the sound insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.
2. Disconnect the electrical connector (2) from the blower motor (1).
3. Remove the screws from the blower motor (1).
4. Remove the blower motor (1) from the HVAC module (3).
5. Remove the retainer from the blower motor impeller. Discard the retainer.
6. Remove the blower motor impeller from the blower motor (1).

Scheme 184

1. Install the blower motor impeller to the blower motor (1).
2. Install the new retainer to the blower motor impeller.
3. Install the blower motor (1) to the HVAC module (3) NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the blower motor (1). Tighten Tighten the screws to 2 N.m (18 lb in).
5. Connect the electrical connector (2) to the blower motor (1).
6. Install the sound insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.

Scheme 185

1. Remove the I/P trim panel. Refer to TRIM PANEL REPLACEMENT - INSTRUMENT PANEL (I/P) UPPER in Instrument Panel, Gages, and Console.
2. Remove the screws (3) from the air distribution duct (1).
3. Remove the air distribution duct (1) from the I/P trim panel (2).

Scheme 186

1. Install the air distribution duct (1) to the I/P trim panel (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the screws (3) to the air distribution duct (1). Tighten Tighten the screws to 2 N.m (18 lb in).
3. Install the I/P trim panel. Refer to TRIM PANEL REPLACEMENT - INSTRUMENT PANEL (I/P) UPPER in Instrument Panel, Gages, and Console.

Scheme 187

1. Remove the instrument panel (I/P) bezel. Refer to BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER in Instrument Panel, Gages, and Console.
2. Remove the knee bolster. Refer to KNEE BOLSTER REPLACEMENT
3. Remove the air deflector housing from the I/P by prying it out.
4. Disconnect the electrical connectors.
5. Remove the air deflector screws.
6. Remove the air deflector from the housing.

Scheme 188

1. Install the air deflector to the housing. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the retaining screws. Tighten Tighten the screws to 1.6 N.m (14 lb in).
3. Connect the electrical connectors.
4. Install the air deflector assembly to the I/P.
5. Remove the knee bolster. Refer to KNEE BOLSTER REPLACEMENT
6. Install the I/P bezel. Refer to BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER in Instrument Panel, Gages, and Console.

Scheme 189

1. Remove the instrument panel (I/P) bezel. Refer to BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER in Instrument Panel, Gages, and Console.
2. Remove the I/P trim panel. Refer to TRIM PANEL REPLACEMENT - INSTRUMENT PANEL (I/P) UPPER in Instrument Panel, Gages, and Console.
3. Remove the deflector mounting screws.
4. Remove the deflector from the I/P.

Scheme 190

1. Install the deflector to the I/P. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the deflector mounting screws. Tighten Tighten the screw to 1.6 N.m (14 lb in).
3. Install the I/P trim panel. Refer to TRIM PANEL REPLACEMENT - INSTRUMENT PANEL (I/P) UPPER in Instrument Panel, Gages, and Console.
4. Install the I/P bezel. Refer to BEZEL REPLACEMENT - INSTRUMENT PANEL (I/P) CLUSTER in Instrument Panel, Gages, and Console.

Scheme 191

1. Use a flat blade tool in order to remove the deflector from the instrument panel.
2. Remove the deflector.

Scheme 192

1. Align the deflector into the opening in the instrument panel.
2. Push the deflector into the instrument panel until the deflector snaps into place.

Scheme 193

Scheme 194

1. Remove the floor console. Refer to CONSOLE REPLACEMENT (WITH CONSOLE MOUNTING BRACKET) or CONSOLE REPLACEMENT (W/O CONSOLE MOUNTING BRACKET) in Instrument Panel, Gages, and Console.
2. Remove the seats. Refer to SEAT REPLACEMENT - CENTER in Seats.
3. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
4. Roll the carpeting back to expose the rear floor air ducts.
5. Remove the rear floor ducts from the floor studs.
6. Remove the rear floor duct.

Scheme 195

Scheme 196

1. Install the rear floor air duct.
2. Install the rear floor ducts from the floor studs.
3. Position the carpeting back into place.
4. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
5. Install the seats. Refer to SEAT REPLACEMENT - CENTER in Seats.
6. Install the floor console. Refer to CONSOLE REPLACEMENT (WITH CONSOLE MOUNTING BRACKET) or CONSOLE REPLACEMENT (W/O CONSOLE MOUNTING BRACKET) in Instrument Panel, Gages, and Console.

Scheme 197

1. Remove the push pin (5) from the left floor air outlet duct (4).
2. Remove the left floor duct (1) from the HVAC module (2).

Scheme 198

1. Install the left floor air outlet duct (1) to the HVAC module (2).
2. Install the push pin (2) to the left floor air outlet duct.

Scheme 199

1. Remove the right closeout/insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.
2. Remove the screw from the right floor air outlet duct (3).
3. Remove the right floor air outlet duct (3) from the HVAC module (2).

Scheme 200

1. Install the right floor air outlet duct (3) to the HVAC module (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the screw to the right floor air outlet duct (3). Tighten Tighten the screw to 1.6 N.m (14 lb in).
3. Install the right closeout/insulator panel. Refer to INSULATOR REPLACEMENT - INSTRUMENT PANEL (I/P) in Instrument Panel, Gages, and Console.

Scheme 201

Scheme 202

Scheme 203

Scheme 204

Scheme 205

Scheme 206

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the electrical connector (3) from the mode actuator (4).
3. Remove the screws from the mode actuator (4).
4. Remove the mode actuator (4) from the HVAC module (1).
5. Remove the wiring harness from the air distribution housing (1).
6. Remove the screws from the air distribution housing (1).
7. Remove the air distribution housing (1) from the HVAC module (2).
8. Remove the screws from the upper recirculation housing (1).
9. Remove the upper recirculation housing (1) from the HVAC module (2).
10. Remove the screws from the lower recirculation housing (1).
11. Remove the lower recirculation housing (1) from the HVAC module (2).
12. Remove the wiring harness from the HVAC module.
13. Remove the screws from the HVAC module.
14. Remove the upper HVAC module case (1) from the lower HVAC module case (2).
15. Remove the right temperature door (2) from the upper HVAC module case (1).

Scheme 207

Scheme 208

Scheme 209

Scheme 210

Scheme 211

Scheme 212

1. Install the right temperature door (2) to the upper HVAC module case (1).
2. Install the upper HVAC module case (1) to the lower HVAC module case (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the screws to the HVAC module. Tighten Tighten the screws to 2 N.m (18 lb in).
4. Install the wiring harness to the HVAC module.
5. Install the lower recirculation housing (1) to the HVAC module (2).
6. Install the screws to the lower recirculation housing (1). Tighten Tighten the screws to 2 N.m (18 lb in).
7. Install the upper recirculation housing (1) to the HVAC module (2).
8. Install the screws to the upper recirculation housing (1). Tighten Tighten the screws to 2 N.m (18 lb in).
9. Install the air distribution housing (1) to the HVAC module (2).
10. Install the screws to the air distribution housing (1). Tighten Tighten the screws to 2 N.m (18 lb in).
11. Install the wiring harness to the air distribution housing (1).
12. Install the mode actuator (4) to the HVAC module (1).
13. Install the screws to the mode actuator (4). Tighten Tighten the screws to 2 N.m (18 lb in).
14. Connect the electrical connector (3) to the mode actuator (4).
15. Install the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 213

Scheme 214

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. If equipped remove the heat stakes (1) from the HVAC module (2) with a screw driver and a hammer.
3. If equipped remove the HVAC module assembly screws.
4. Remove the upper HVAC module case (1) from the lower HVAC module case (2).
5. Remove the right temperature door (4) from the upper HVAC module case (3).

Scheme 215

1. Install the right temperature door (4) to the upper HVAC module case (3).
2. Install the upper HVAC module case (1) to the lower HVAC module case (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices. Important: For every heat stake removed ensure that you install a screw.
3. Install the screws to the HVAC module assembly. Tighten Tighten the screws to 1.6 N.m (14 lb in).
4. Install the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 216

Scheme 217

Scheme 218

Scheme 219

Scheme 220

Scheme 221

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the electrical connector (3) from the mode actuator (4).
3. Remove the screws from the mode actuator (4).
4. Remove the mode actuator (4) from the HVAC module (1).
5. Remove the wiring harness from the air distribution housing (1).
6. Remove the screws from the air distribution housing (1).
7. Remove the air distribution housing (1) from the HVAC module (2).
8. Remove the screws from the upper recirculation housing (1).
9. Remove the upper recirculation housing (1) from the HVAC module (2).
10. Remove the screws from the lower recirculation housing (1).
11. Remove the lower recirculation housing (1) from the HVAC module (2).
12. Remove the wiring harness from the HVAC module.
13. Remove the screws from the HVAC module.
14. Remove the upper HVAC module case (1) from the lower HVAC module case (2).
15. Remove the HVAC module chamber plate (1) from the lower HVAC module case (3).
16. Remove the left temperature door (2) from the lower HVAC module case (3).

Scheme 222

Scheme 223

Scheme 224

Scheme 225

Scheme 226

Scheme 227

1. Install the left temperature door (2) to the lower HVAC module case (3).
2. Install the HVAC module chamber plate (1) to the lower HVAC module case (3).
3. Install the upper HVAC module case (1) to the lower HVAC module case (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the HVAC module. Tighten Tighten the screws to 2 N.m (18 lb in).
5. Install the wiring harness to the HVAC module.
6. Install the lower recirculation housing (1) to the HVAC module (2).
7. Install the screws to the lower recirculation housing (1). Tighten Tighten the screws to 2 N.m (18 lb in).
8. Install the upper recirculation housing (1) to the HVAC module (2).
9. Install the screws to the upper recirculation housing (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
10. Install the air distribution housing (1) to the HVAC module (2).
11. Install the screws to the air distribution housing (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
12. Install the wiring harness to the air distribution housing (1).
13. Install the mode actuator (4) to the HVAC module (1).
14. Install the screws to the mode actuator (4). Tighten: Tighten the screws to 2 N.m (18 lb in).
15. Connect the electrical connector (3) to the mode actuator (4).
16. Install the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 228

Scheme 229

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. If equipped remove the heat stakes (1) from the HVAC module (2) with a screw driver and a hammer.
3. If equipped remove the HVAC module assembly screws.
4. Remove the upper HVAC module case (3) from the lower HVAC module case (10).
5. Remove the air temperature separator plate (5) from the lower HVAC module case (10).
6. Remove the left temperature door (11) from the lower HVAC module case (10).

Scheme 230

1. Install the left temperature door (11) to the lower HVAC module case (10).
2. Install the air temperature separator plate (5) to the lower HVAC module case (10).
3. Install the upper HVAC module case (3) to the lower HVAC module case (10). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices. Important: For every heat stake removed ensure that you install a screw.
4. Install the screws to the HVAC module assembly. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
5. Install the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 231

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Separate the HVAC module assembly.
3. Remove the mode actuator screws.
4. Remove the mode actuator (3).
5. Remove the mode actuator cam assembly (4).
6. Remove the defroster door lever (2).
7. Remove the defroster door (1).

Scheme 232

1. Install the defroster door (1)
2. Install the defroster door lever (2).
3. Install the mode actuator cam assembly (4).
4. Install the mode actuator (3).
5. Install the mode actuator screws. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
6. Install the mode actuator screws. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
7. Install the HVAC module assembly halves.
8. Install the screws to the HVAC module assembly. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
9. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 233

Scheme 234

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. If equipped remove the heat stakes (1) from the HVAC module (2) with a screw driver and a hammer.
3. If equipped remove the HVAC module assembly screws.
4. Separate the HVAC module assembly.
5. Remove the mode actuator screws.
6. Remove the mode actuator.
7. Remove the mode actuator cam assembly.
8. Remove the defroster door (8).

Scheme 235

1. Install the defroster door (8).
2. Install the mode actuator cam assembly.
3. Install the mode actuator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the mode actuator screws. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
5. Install the HVAC module assembly halves. Important: For every heat stake removed ensure that you install a screw.
6. Install the screws to the HVAC module assembly. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
7. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 236

Scheme 237

Scheme 238

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the electrical connector (3) from the mode actuator (4).
3. Remove the screws from the mode actuator (4).
4. Remove the mode actuator (4) from the HVAC module assembly (1).
5. Remove the wiring harness from the air distribution housing (1).
6. Remove the screws from the air distribution housing (1).
7. Remove the air distribution housing (1) from the HVAC module assembly (2).
8. Remove the mode door (2) from the air distribution housing (1).

Scheme 239

Scheme 240

Scheme 241

1. Install the mode door (1) to the air distribution housing (1).
2. Install the air distribution housing (1) to the HVAC module assembly (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the screws to the air distribution housing (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
4. Install the wiring harness to the air distribution housing (1).
5. Connect the electrical connector (3) to the mode actuator (4).
6. Install the screws to the mode actuator (4).
7. Install the mode actuator (4) to the HVAC module assembly (1).
8. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 242

Scheme 243

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. If equipped remove the heat stakes (1) from the HVAC module (2) with a screw driver and a hammer.
3. If equipped remove the HVAC module assembly screws.
4. Separate the HVAC module assembly.
5. Remove the air temperature separator plate (5) from the HVAC module assembly (10).
6. Remove the lower mode door (9) from the HVAC module assembly (10).

Scheme 244

1. Install the lower mode door (9) to the HVAC module assembly (10).
2. Install the air temperature separator plate (5) to the HVAC module assembly (10).
3. Install the HVAC module assembly halves. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices. Important: For every heat stake removed ensure that you install a screw.
4. Install the screws to the HVAC module assembly. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
5. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 245

Scheme 246

Scheme 247

Scheme 248

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the electrical connector (3) from the mode actuator (4).
3. Remove the screws from the mode actuator (4).
4. Remove the mode actuator (4) from the HVAC module assembly (1).
5. Remove the wiring harness from the air distribution housing (1).
6. Remove the screws from the air distribution housing (1).
7. Remove the air distribution housing (1) from the HVAC module assembly (2).
8. Remove the screws from the air distribution housing (1).
9. Separate the air distribution housing halves.
10. Remove the lever from the upper mode door (4).
11. Remove the lever from the defrost door (2).
12. Remove the door assembly (3) from the left air distribution housing (1).
13. Remove the mode door (4) from the door assembly (3).

Scheme 249

Scheme 250

Scheme 251

Scheme 252

1. Install the mode door (4) to the door assembly (3).
2. Install the door assembly (3) to the left air distribution housing (1).
3. Install the lever to the defrost door (2).
4. Install the lever to the upper mode door (4).
5. Install the air distribution housing halves. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
6. Install the screws to the air distribution housing (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
7. Install the air distribution housing (1) to the HVAC module assembly (2).
8. Install the screws to the air distribution housing (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
9. Install the wiring harness to the air distribution housing (1).
10. Connect the electrical connector (3) to the mode actuator (4).
11. Install the mode actuator (4) to the HVAC module assembly (1).
12. Install the screws to the mode actuator (4). Tighten: Tighten the screws to 2 N.m (18 lb in).
13. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Removal Procedure

Important: The upper mode door (6) is serviced with the upper HVAC module case (3).

Scheme 253

Scheme 254

1. Remove the HVAC module. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the electrical connector (3) from the mode actuator (4).
3. Remove the screws from the mode actuator (4).
4. Remove the mode actuator (4) from the HVAC module assembly (1).
5. If equipped remove the heat stakes (1) from the HVAC module (2) with a screw driver and a hammer.
6. If equipped remove the HVAC module assembly screws.
7. Separate the HVAC module assembly.
8. Remove the lever (7) from the upper mode door/upper HVAC module case (6).

Scheme 255

1. Install the lever (7) to the upper mode door/upper HVAC module case (6).
2. Install the HVAC module assembly halves. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices. Important: For every heat stake removed ensure that you install a screw.
3. Install the screws to the HVAC module assembly. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
4. Install the mode actuator to the HVAC module assembly.
5. Install the screws to the mode actuator. Tighten Tighten the screws to 1.6 N.m (14 lb in).
6. Connect the electrical connector to the mode actuator.
7. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 256

Scheme 257

Scheme 258

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the wiring harness from the recirculation housing (1).
3. Remove the screws from the upper recirculation housing (1).
4. Remove the upper recirculation housing (1) from the HVAC module assembly (2).
5. Disconnect the electrical connector from the recirculation actuator (1).
6. Remove the screws from the recirculation actuator (1).
7. Remove the recirculation actuator (1) from the recirculation housing (2).
8. Remove the recirculation door (1) from the recirculation housing (2).

Scheme 259

Scheme 260

Scheme 261

1. Install the recirculation door (1) to the recirculation housing (2).
2. Install the recirculation actuator (1) to the recirculation housing (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the screws to the recirculation actuator (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
4. Connect the electrical connection to the recirculation actuator (1).
5. Install the upper recirculation housing (1) to the HVAC module assembly (2).
6. Install the screws to the upper recirculation housing (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
7. Install the wiring harness to the recirculation housing (1).
8. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 262

Scheme 263

Scheme 264

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Disconnect the recirculation actuator electrical connection (1).
3. Remove the recirculation actuator mounting screws.
4. Remove the recirculation actuator.
5. Remove the recirculation door.

Scheme 265

Scheme 266

Scheme 267

1. Install the recirculation door.
2. Install the recirculation actuator. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the recirculation actuator mounting screws. Tighten: Tighten the screws to 1.9 N.m (17 lb in).
4. Connect the recirculation actuator electrical connection (1).
5. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 268

Scheme 269

Scheme 270

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the screws from the heater core cover.
3. Remove the heater core cover (1) from the HVAC module assembly (2).
4. Remove the heater core cowl gasket (1) from the heater core (2).
5. Remove the heater core (1) from the HVAC module assembly (2).

Scheme 271

Scheme 272

Scheme 273

1. Install the heater core (1) to the HVAC module assembly (2).
2. Install the heater core cowl gasket (1) to the HVAC module assembly (2).
3. Install the heater core cover (1) to the HVAC module assembly (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the heater core cover (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
5. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 274

Scheme 275

1. Remove the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the screws from the heater core cover.
3. Remove the heater core cover (1) from the HVAC module assembly (2).
4. Remove the heater core cowl gasket (1) from the heater core (2).
5. Remove the heater core (2) from the HVAC module assembly (3).

Scheme 276

Scheme 277

1. Install the heater core (2) to the HVAC module assembly (3).
2. Install the heater core cowl gasket (1) to the heater core (2).
3. Install the heater core cover (1) to the HVAC module assembly (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the screws to the heater core cover (1). Tighten: Tighten the screws to 2 N.m (18 lb in).
5. Install the HVAC module assembly. Refer to «HVAC MODULE ASSEMBLY REPLACEMENT»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 278

Scheme 279

Scheme 280

Scheme 281

Scheme 282

Scheme 283

Scheme 284

1. Drain the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
2. Squeeze the plastic retainer tabs on the inlet hose.
3. Pull the connection apart.
4. Squeeze the plastic retainer tabs on the outlet hose.
5. Pull the connection apart.
6. Remove the auxiliary heater pipes (1, 2) from the heater inlet and outlet tees (3, 4).
7. Remove both of the right tires. Refer to TIRE AND WHEEL REMOVAL AND INSTALLATION in Tires and Wheels.
8. Remove the right rear wheelhouse panel. Refer to WHEELHOUSE INNER PANEL EXTENSION REPLACEMENT - REAR in Body Rear End.
9. Remove the right front wheelhouse panel. Refer to WHEELHOUSE PANEL REPLACEMENT in Body Front End.
10. Remove the auxiliary heater pipes (2, 3) from the auxiliary heater core.
11. Remove the heater/A/C tubes retaining nut (4) from the stud (1) at the frame (6).
12. Remove the auxiliary heater pipes (2) from the clamps (5).
13. Remove the auxiliary heater pipes from the vehicle.

Scheme 285

Scheme 286

Scheme 287

Scheme 288

1. Install the auxiliary heater pipes to the vehicle.
2. Install the auxiliary heater pipes (2) to the clamps (5). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the heater/A/C tubes retaining nut (4) to the stud (1) at the frame (6). Tighten: Tighten the nut to 7 N.m (62 lb in).
4. Install the auxiliary heater pipes (2, 3) to the auxiliary heater core.
5. Install the right front wheelhouse panel. Refer to WHEELHOUSE PANEL REPLACEMENT in Body Front End.
6. Install the right rear wheelhouse panel. Refer to WHEELHOUSE INNER PANEL EXTENSION REPLACEMENT - REAR in Body Rear End.
7. Install both of the right tires. Refer to TIRE AND WHEEL REMOVAL AND INSTALLATION in Tires and Wheels.
8. Install the auxiliary heater pipes (1, 2) to the heater inlet and outlet tees (3, 4).
9. Connect the outlet heater hose to the heater core.
10. Connect the inlet heater hose to the heater core.
11. Fill the cooling system. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.

Scheme 289

1. Remove the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
2. Disconnect the electrical connector from the blower motor resistor.
3. Remove the retaining screws from the blower motor resistor.
4. Remove the blower motor resistor (1) from the vehicle.

Scheme 290

1. Install the blower motor resistor (1) to the vehicle. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Install the retaining screws to the blower motor resistor. Tighten: Tighten the screws to 1.9 N.m (17 lb in).
3. Connect the electrical connector to the blower motor resistor.
4. Install the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.

Scheme 291

1. Remove the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
2. Disconnect the electrical connectors.
3. Remove the blower motor screws.
4. Remove the blower motor (1) from the auxiliary HVAC module (2).
5. Remove the retaining clip from the fan cage.
6. Remove the fan cage from the blower motor.

Scheme 292

1. Install the fan cage to the blower motor (1).
2. Install the retaining clip to the fan cage.
3. Install the blower motor (1) to the auxiliary HVAC module (2). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
4. Install the blower motor screws. Tighten: Tighten the screws to 1.9 N.m (17 lb in).
5. Connect the electrical connectors.
6. Install the right rear quarter trim. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.

Scheme 293

1. Remove the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
2. Remove the upper air temperature sensor, if equipped.
3. Remove the upper air duct fastener (5).
4. Remove the duct (6) from the vehicle.

Scheme 294

1. Install the duct (6) to the vehicle.
2. Install the upper air duct fastener (5).
3. Install the upper air temperature sensor, if equipped.
4. Install the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.

Scheme 295

1. Remove the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
2. Remove the air temperature sensor, if equipped.
3. Remove the lower air duct fastener.
4. Remove the lower air duct (5) from the vehicle.

Scheme 296

1. Install the air duct (5) to the vehicle.
2. Install the lower air duct fastener.
3. Install the air temperature sensor, if equipped.
4. Install the left rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.

Scheme 297

1. Turn the air deflector louver counter clockwise in order to release it from the headliner.
2. Remove the air deflector louver from the vehicle.

Scheme 298

1. Align the air deflector louver into the opening in the headliner.
2. Turn the air deflector louver clockwise in order to retain it to the headliner.

Scheme 299

Scheme 300

Scheme 301

Scheme 302

1. Remove the auxiliary HVAC module (4) from the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning)
2. Remove the air temperature actuator (1) from the auxiliary HVAC module.
3. Remove the heater core cover (1) from the auxiliary HVAC module.
4. Remove the heater core (1) from the auxiliary HVAC module.

Scheme 303

Scheme 304

Scheme 305

Scheme 306

1. Install the heater core (1) to the auxiliary HVAC module.
2. Install the heater core cover (1) to the auxiliary HVAC module.
3. Install the air temperature actuator (1) to the auxiliary HVAC module.
4. Install the auxiliary HVAC module assembly (4) to the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning)

Scheme 307

Scheme 308

Scheme 309

Scheme 310

1. Remove the auxiliary HVAC module (3) from the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the air temperature actuator (1) from the auxiliary HVAC module.
3. Remove the stud on the underside of the auxiliary HVAC module between the heater core inlet and outlet pipes.
4. Carefully separate the heater core pipe gasket from the module case and remove the heater core pipe retainer.
5. Remove the auxiliary HVAC module lower cover.
6. Remove the heater core clamp.
7. Remove the heater core from the auxiliary HVAC module.

Scheme 311

Scheme 312

Scheme 313

Scheme 314

1. Install the heater core to the auxiliary HVAC module.
2. Install the heater core clamp.
3. Install the auxiliary HVAC module lower cover.
4. Install the heater core pipe retainer and gasket.
5. Install the stud between the heater core inlet and outlet on the underside of the rear HVAC module.
6. Install the air temperature actuator (1) to the auxiliary HVAC module.
7. Install the auxiliary HVAC module assembly (3) to the vehicle.

Scheme 315

1. Remove the evaporator core. Refer to «EVAPORATOR CORE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «EVAPORATOR CORE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Carefully remove the sealer packed around the Thermal Expansion Valve (TXV). Reuse the sealer on the replacement TXV. Important: Note the mounting location and the orientation of the tube on the core.
3. Remove the clip retaining the capillary tube to the evaporator core.
4. Disconnect the evaporator tube connections from the TXV.
5. Remove the TXV from the tubes.

Scheme 316

1. Install the TXV to the tubes. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
2. Connect the evaporator tube connections from the TXV. Tighten: Tighten the tube connections to 28 N.m (21 lb ft). Important: Install the clip and the tube in the location and the orientation as noted during the disassembly.
3. Install the clip in order to retain the capillary tube to the evaporator core.
4. Pack sealer around the TXV in the manner found during the disassembly.
5. Install the evaporator core. Refer to «EVAPORATOR CORE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «EVAPORATOR CORE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 317

Scheme 318

Scheme 319

Scheme 320

Scheme 321

Scheme 322

Scheme 323

1. Recover the refrigerant from the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Drain the engine coolant. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
3. Raise the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
4. Disconnect the heater lines (2,3) from the auxiliary HVAC module at the underside of the vehicle.
5. Disconnect the air conditioning lines (2,3) from the auxiliary HVAC module at the underside of the vehicle.
6. Remove the nuts (2) from the studs (1) that secure the auxiliary HVAC module to the underside of the vehicle.
7. Remove the safety stands.
8. Lower the vehicle.
9. Remove the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
10. Remove the electronic suspension control module. Refer to ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (TAHOE/YUKON/ESCALADE) or ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (ESCALADE EXT) in Electronic Suspension Control.
11. Disconnect the electrical connectors from the auxiliary HVAC module.
12. Remove the fastener (5) for the upper auxiliary air duct (6). Carefully slide the duct up, into the headliner, until the bottom edge of the duct is above the air distributor duct.
13. Remove the fastener (4) for the lower auxiliary air outlet (5).
14. Remove the fastener (4) for the air distributor duct (3).
15. Remove the air distributor duct (3).
16. Remove the fasteners (2,4) retaining the auxiliary HVAC module to the vehicle.
17. Remove the auxiliary HVAC module (3) from the vehicle.

Scheme 324

Scheme 325

Scheme 326

Scheme 327

Scheme 328

Scheme 329

Scheme 330

1. Install the auxiliary HVAC module assembly (3) to the vehicle.
2. Install the two bolts (2,4) inside the vehicle in order to retain the auxiliary HVAC module to the vehicle.
3. Install the air distributor duct (3).
4. Install the fastener (4)
5. Install the lower auxiliary air outlet (5).
6. Install the fastener (4)
7. Install the upper auxiliary air duct (6) to the air distributor duct (3).
8. Install the fastener (5)
9. Connect the electrical connectors to the auxiliary HVAC module.
10. Install the electronic suspension control module. Refer to ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (TAHOE/YUKON/ESCALADE) or ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (ESCALADE EXT) in Electronic Suspension Control.
11. Install the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
12. Raise the vehicle. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
13. Install the nuts (2) that secure the auxiliary HVAC module to the vehicle. Tighten: Tighten the nuts to 9 N.m (80 lb in).
14. Install the air conditioning lines (2,3) and the nut (4) to the auxiliary HVAC module. Tighten: Tighten the nut to 16 N.m (12 lb ft).
15. Install the heater lines (2,3) to the auxiliary HVAC module at the underside of vehicle.
16. Remove the safety stands.
17. Lower the vehicle.
18. Fill the engine coolant. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
19. Recharge the refrigerant to the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

J 39400-A Halogen Leak Detector

Scheme 331

Scheme 332

Scheme 333

Scheme 334

Scheme 335

1. Recover the refrigerant from the A/C system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Drain the engine coolant. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
3. Raise the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
4. Disconnect the heater lines (2,3) from the auxiliary HVAC module at the underside of the vehicle.
5. Disconnect the air conditioning lines (2,3) from the auxiliary HVAC module at the underside of the vehicle.
6. Remove the nuts (2) from the studs (1) that secure the auxiliary HVAC module to the underside of the vehicle.
7. Lower the vehicle.
8. Remove the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
9. Remove the electronic suspension control module. Refer to ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (TAHOE/YUKON/ESCALADE) or ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (ESCALADE EXT) in Electronic Suspension Control.
10. Disconnect the electrical connectors from the Auxiliary HVAC module.
11. Remove the fastener (5) for the upper auxiliary air duct (1). Carefully slide the duct up, into the headliner, until the bottom edge of the duct is above the air distributor duct.
12. Remove the fasteners (3) retaining the auxiliary HVAC module to the vehicle.
13. Remove the auxiliary HVAC module (4) from the vehicle.

Scheme 336

Scheme 337

Scheme 338

Scheme 339

Scheme 340

1. Install the auxiliary HVAC module assembly (4) to the vehicle.
2. Install the two bolts (3) inside the vehicle in order to retain the auxiliary HVAC module to the vehicle.
3. Install the upper auxiliary air duct (1) to the air distributor duct. Install the fastener (5).
4. Connect the electrical connectors to the auxiliary HVAC module.
5. Install the electronic suspension control module. Refer to ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (TAHOE/YUKON/ESCALADE) or ELECTRONIC SUSPENSION CONTROL MODULE REPLACEMENT (ESCALADE EXT) in Electronic Suspension Control.
6. Install the right rear quarter trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (UTILITY) or TRIM PANEL REPLACEMENT - REAR QUARTER - RIGHT (SUBURBAN) in Interior Trim.
7. Raise the vehicle. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
8. Install the nuts (2) that secure the auxiliary HVAC module to the vehicle. Tighten: Tighten the nuts to 9 N.m (80 lb in).
9. Install the air conditioning lines (2,3) and the nut (4) to the auxiliary HVAC module. Tighten: Tighten the nut to 16 N.m (12 lb ft).
10. Install the heater lines (2,3) to the auxiliary HVAC module at the underside of vehicle.
11. Lower the vehicle.
12. Fill the engine coolant. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
13. Recharge the refrigerant to the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
14. Leak test the fittings of the component using the J 39400-A .

J 39400-A Halogen Leak Detector

Scheme 341

Scheme 342

Scheme 343

Scheme 344

Scheme 345

Scheme 346

1. Remove the auxiliary HVAC module (4) from the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the air temperature actuator (1) from the auxiliary HVAC module.
3. Remove the heater core cover (1) from the auxiliary HVAC module.
4. Remove the heater core (1) from the auxiliary HVAC module.
5. Remove the lower module cover from the auxiliary HVAC module.
6. Remove the evaporator core from the lower module cover.

Scheme 347

Scheme 348

Scheme 349

Scheme 350

Scheme 351

Scheme 352

1. Install the evaporator core to the lower module cover.
2. Install the lower module cover to the auxiliary HVAC module.
3. Install the heater core (1) to the auxiliary HVAC module.
4. Install the heater core cover (1) to the auxiliary HVAC module.
5. Install the air temperature actuator (1) to the auxiliary HVAC module.
6. Install the auxiliary HVAC module assembly (4) to the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

J 39400-A Halogen Leak Detector

Scheme 353

Scheme 354

Scheme 355

Scheme 356

Scheme 357

1. Remove the auxiliary HVAC module (3) from the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the air temperature actuator (1).
3. Remove the stud on the underside of the rear HVAC module between the heater core inlet and outlet pipes (4).
4. Carefully separate the heater core pipe gasket from the module case and remove the heater core pipe retainer.
5. Remove the screws from the HVAC module lower cover.
6. Remove the auxiliary HVAC module lower cover.
7. Remove the heater core clamp.
8. Remove the heater core from the auxiliary HVAC module.
9. Carefully remove the gasket between the auxiliary HVAC module and the air distributor duct. This gasket will be re-used if possible.
10. Remove the fasteners and separate the front case half from the back half.
11. Remove the evaporator core from the back case half.
12. Inspect the gaskets and the seals for damage.
13. Replace the gaskets and the seals, as needed.

Scheme 358

Scheme 359

Scheme 360

Scheme 361

Scheme 362

1. Install the evaporator core into the case.
2. Install the evaporator core seal. Important: Ensure the proper positioning of the air distributor duct gasket and the temperature door during assembly.
3. Reassemble the case halves.
4. Install the heater core to the auxiliary HVAC module.
5. Install the heater core clamp.
6. Install the auxiliary HVAC module lower cover. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
7. Install the screws to the HVAC module lower cover. Tighten: Tighten the screws to 1.6 N.m (14 lb in).
8. Install the heater core pipe retainer and gasket.
9. Install the stud between the heater core inlet and outlet on the underside of the auxiliary HVAC module.
10. Install the air temperature actuator (1).
11. Install the auxiliary HVAC module (3) to the vehicle. Refer to «HVAC MODULE REPLACEMENT - AUXILIARY (SUBURBAN/YUKON XL)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) or «HVAC MODULE REPLACEMENT - AUXILIARY (TAHOE/YUKON)»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

J 39400-A Halogen Leak Detector

Scheme 363

Scheme 364

Scheme 365

1. Recover the refrigerant from the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Remove the auxiliary A/C evaporator tubes (3) from the condenser tube (2) and the accumulator (5).
3. Loosen the right front wheelhouse to gain access to the clamp behind the wheelhouse.
4. Raise the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
5. Remove the retaining nut (2) and the auxiliary A/C evaporator tubes (3) from the auxiliary HVAC module.
6. Remove the heater/A/C tubes retaining nut (4) from the stud (1) at the frame (6).
7. Remove the auxiliary A/C evaporator tubes (3) from the clamps (5).
8. Remove the auxiliary A/C evaporator tubes from the vehicle.

Scheme 366

Scheme 367

Scheme 368

1. Install the auxiliary A/C evaporator tubes to the vehicle.
2. Install the auxiliary A/C evaporator tubes (3) to the clamps (5). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/avalanche/i-2001-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) in Cautions and Notices.
3. Install the heater/A/C tubes retaining nut (4) to the stud (1) at the frame (6). Tighten: Tighten the nut to 7 N.m (62 lb in).
4. Install the auxiliary A/C evaporator tubes (2, 3) and the retaining nut to the auxiliary HVAC module. Tighten: Tighten the nut to 16 N.m (12 lb ft).
5. Lower the vehicle.
6. Install the right front wheelhouse. Refer to WHEELHOUSE PANEL REPLACEMENT in Body Front End.
7. Install the auxiliary A/C evaporator tubes (3) to the condenser tube (2) and the accumulator (5). Tighten: Tighten the nuts to 16 N.m (12 lb ft).
8. Recharge the refrigerant to the system. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
9. Leak test the fittings of the component using the J 39400-A .

J 41425 A/C Line Repair Kit

Do not service the rear A/C or heater lines as a complete unit. Service the rear A/C or heater lines as a sectional repair.

You can obtain the various sections of line through GMSPO.

Use the J 41425 when any of the following actions damage the rear A/C or heater lines

1. Rub-through
2. Collision damage
3. Leakage in the system

Minimum Tube Length Required Table

Important: When you section the rear A/C or heater lines, ensure that the correct minimum length remains in the straight part of the line on both sides of the splice.

Follow the Straight Line Repair procedure in order to repair line damage in a straight section of line.

Follow the Line Sectioning Repair procedure in order to repair any damage in a bend area. Do not repair the rear A/C or heater lines in a bend area, replace the lines. Maintaining the original line shape will prevent vibrations and rub-through.

Scheme 369

Straight Line Repair

1. Recover the refrigerant, if repairing the A/C lines. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Drain the coolant, if repairing the heater lines. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
3. Raise and support the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
4. Locate the area that requires repair.
5. Obtain a length of replacement line to make the repair.
6. Use a tubing cutter in order to cut and remove the section of damaged line. Important: The length of the replacement line must be the same as the section being replaced.
7. Use a tubing cutter in order to cut the replacement line to length.
8. Use the cleaning pad from the J 41425 in order to clean any burrs or grease from the line ends. Be sure to clean at least 19 mm (0.75 in) from the line ends.
9. Use the LOK prep sealant in order to prep the line ends.
10. Apply one drop of the J 41425-3 sealing compound to the outside of each end of the line.
11. Insert the line ends into the LOK fitting.
12. Rotate the LOK fitting one complete turn in order to evenly distribute the sealing compound around the lines.
13. Install the correct LOK fitting jaws into the J 41425-1 tool.
14. Install the J 41425-1 tool over the LOK connectors. Verify that the LOK connector ends are positioned in the counter bores of the jaws. Important: Hold the J 41425-1 tool body with a 3/8" breaker bar.
15. Tighten the forcing screw of the J 41425-1 tool. When fully seated, the LOK connector collars will bottom out on the center shoulder of the LOK fitting.
16. Loosen the forcing screw and remove the J 41425-1 tool from the repaired line.
17. Repeat Step 8 through Step 16 to repair the other end of the line.
18. Verify that the LOK fittings are correctly installed.
19. Lower the vehicle.
20. Refill the coolant, if drained. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
21. Evacuate and recharge the refrigerant, if repairing the A/C lines. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Line Sectioning Repair

1. Recover the refrigerant, if repairing the A/C lines. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .
2. Drain the coolant, if repairing the heater lines. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
3. Raise and support the vehicle. Refer to «LIFTING AND JACKING THE VEHICLE»(/chevrolet/avalanche/i-2001-2006/remont/hoistjack/#jacking-and-lifting-avalanche__lifting-and-jacking-the-vehicle) in General Information.
4. Obtain a new A/C or heater line for sectioning. Important: Stagger the splices if repairing more than one line.
5. Scribe a mark on the line that will be sectioned.
6. Use a tubing cutter in order to cut the line or lines being replaced.
7. Remove the section of line being replaced from the vehicle. Important: The length of the replacement line must be the same as the line being replaced.
8. Install the replacement line to the vehicle.
9. Use a tubing cutter in order to cut the replacement line to length.
10. Use the cleaning pad from the J 41425 in order to clean any burrs or grease. Be sure to clean at least 19 mm (0.75 in) from the A/C line.
11. Use the LOK prep sealant in order to prep the A/C or heater line.
12. Apply one drop of the J 41425-3 sealing compound to the outside of each line end.
13. Insert the line ends into the LOK fitting.
14. Rotate the LOK fitting one complete turn in order to evenly distribute the sealing compound around the lines.
15. Install the correct LOK fitting jaws into the J 41425-1 tool.
16. Install the J 41425-1 tool over the LOK connectors. Verify that the LOK connector ends are positioned in the counter bores of the jaws.
17. Hold the tool body with a 3/8" breaker bar. Turn the forcing screw until both of the connector collars bottom on the center shoulder of the LOK fitting.
18. Loosen the forcing screw. Remove the tool from the repaired line.
19. Verify that the LOK fitting is correctly installed.
20. Lower the vehicle.
21. Refill the coolant, if drained. Refer to DRAINING AND FILLING COOLING SYSTEM in Engine Cooling.
22. Evacuate and recharge the refrigerant, if repairing the A/C lines. Refer to «REFRIGERANT RECOVERY AND RECHARGING»(/chevrolet/avalanche/i-2001-2006/remont/manual-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 370

Scheme 371

Scheme 372

Scheme 373

See also:
• LIFTING AND JACKING THE VEHICLE
• FASTENER NOTICE
• DRIVE BELT REPLACEMENT -- AIR CONDITIONING
• REFRIGERANT RECOVERY AND RECHARGING