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Heating, Ventilation and Air Conditioning Buick LaCrosse I

Automatic HVAC System 22 illustrations ~11154 words

Fastener Tightening Specifications

ApplicationSpecification
MetricEnglish
A/C Compressor Clutch Bolt12 N.m106 lb in
A/C Compressor Drain Plug16 N.m12 lb ft
A/C Compressor Front Bolt50 N.m36 lb ft
A/C Compressor Front Nut50 N.m36 lb ft
A/C Compressor Hose to A/C Compressor Block Fitting Nut17 N.m12.5 lb ft
A/C Compressor Hose to A/C Condenser Nut17 N.m12.5 lb ft
A/C Compressor Hose to Evaporator Tube Block Fitting Nut17 N.m12.5 lb ft
A/C Compressor Pressure Relief Valve8 N.m70 lb in
A/C Compressor Rear Bolt50 N.m36 lb ft
A/C Refrigerant Pressure Sensor4.7 N.m41 lb in
Air Distributor Case Cover Screws1.5 N.m13 lb in
Air Duct Bolts10 N.m89 lb in
Air Duct Center Screw1.8 N.m16 lb in
Blower Motor Screws1.5 N.m13 lb in
Blower Motor Control Module Screws1.5 N.m13 lb in
Evaporator Line Block Fitting-to-TXV Nut17 N.m12.5 lb ft
Heater Core Cover Screws1.5 N.m13 lb in
Heater Core Outlet Cover Screws1.5 N.m13 lb in
Heater Inlet Pipe Adapter Bolt7 N.m62 lb in
Heater Outlet Pipe Adapter Bolt7 N.m62 lb in
HVAC Module-to-Dash Bolts/Nuts10 N.m89 lb in
HVAC Module Upper Case Screws1.5 N.m13 lb in
I/P Center Air Outlet Screw2 N.m18 lb in
I/P Cluster Trim Bezel Assembly Screw2 N.m18 lb in
Side Window Defog Outlet Grille Screw2 N.m18 lb in
TXV-to-Evaporator Screws7 N.m62 lb in

Fastener Tightening Specifications

Refrigerant System Capacities

ApplicationSpecification
MetricEnglish
Abrupt Refrigerant Loss60 ml 12.0 oz. 1
PAG Oil GM P/N 12378526 for United States PAG Oil GM P/N 88900060 for Canada
Compressor Replacement
IMPORTANT: Compressor failure can occur if the oil removed during refrigerant recovery is not replaced. The 7CVC service compressor is shipped with 150 ml 2 (5 oz. 2 ) of PAG oil.
Condenser Replacement30 ml 21.0 oz. 2
Evaporator Replacement90 ml 23.0 oz. 2
Any Line Set (Hose/Tube or Tube Assembly) Replacement30 ml 21.0 oz. 2
Total System PAG Oil Capacity150.0 ml5 oz.
R-134a
Refrigerant Charge0.61 kg1.35 lb
1 Abrupt refrigerant loss due to large leak, hose rupture, collision, or pressure relief valve opening. Conditions that allow the refrigerant to seep or bleed off over time do not cause this oil loss. Upon replacement of a component that caused a large refrigerant loss, also add the required amount of oil for the particular component. 2 If more than the specified amount of PAG oil was drained from a component, add the amount drained.
IMPORTANT
Compressor failure can occur if the oil removed during refrigerant recovery is not replaced.

Refrigerant System Capacities

Begin the system diagnosis with Diagnostic System Check - Vehicle in Vehicle DTC Information. The Diagnostic System Check - Vehicle will provide the following information

  1. The identification of the control modules which are not communicating
  2. The identification of any stored DTCs and their status

The use of the Diagnostic System Check - Vehicle will identify the correct procedures to begin vehicle diagnosis. These must be performed before system DTC or symptom diagnosis.

Tools Required

  1. J 39400-A Halogen Leak Detector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  2. J 41447 R-134A A/C Tracer Dye-Box of 24. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  3. J 42220 Universal 12V Leak Detection Lamp. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  4. J 43872 Fluorescent Dye Cleaner. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  5. J 46297 A/C Dye Injector Kit. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  6. J 46297-12 Replacement Dye Cartridges. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Refrigerant Leak Testing

IMPORTANTGeneral Motors vehicles are now manufactured with fluorescent dye installed directly into the air conditioning (A/C) system.

The fluorescent dye mixes and flows with the polyalkylene glycol (PAG) oil throughout the refrigerant system.

Verifying some passive leaks may require using the J 39400-A , even though the A/C system contains fluorescent dye. See Special Tools .

The only time that adding additional fluorescent dye is required is after flushing the A/C system.

Fluorescent Leak Detector

Fluorescent dye will assist in locating any leaks in the A/C system.

  1. 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.
  2. Leaks in the A/C system will be indicated in a light green or yellow color when using the leak detection lamp. Use the leak detection lamp in the following areas: All fittings or connections that use seal washers or O-rings All of the A/C components The A/C compressor shaft seal The A/C hoses and pressure switches The HVAC module drain tube, if the evaporator core is suspected of leaking The service port sealing caps The sealing cap is the primary seal for the service ports.
  3. Follow the instructions supplied with the J 42220 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  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 J 43872 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Fluorescent Dye Injection

  1. Not all of the fluorescent dyes are compatible with PAG oil. Some types of dye 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.
  3. To prevent false diagnosis, thoroughly clean any residual dye from the service port with a rag and the approved fluorescent dye cleaner J 43872 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Halogen Leak Detector

CAUTIONDo not operate the detector in a combustible atmosphere since its sensor operates at high temperatures or personal injury and/or damage to the equipment may result.

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.

IMPORTANTHalogen leak detectors are sensitive to the following items: Windshield washing solutions Many solvents and cleaners Some adhesives used in the vehicle

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

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

Follow the instructions supplied with the J 39400-A . See Special Tools .

Test Description

This test measures the operating efficiency of the A/C system under the following conditions

  1. The current ambient air temperature (AAT)
  2. The current relative humidity
  3. The high side pressure of the A/C system
  4. The low side pressure of the A/C system
  5. The temperature of the air being discharged into the passenger compartment

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

  1. 1: This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.
  2. 2: This step measures the performance of the A/C system.
  3. 3: This step is to allow for vehicle variations as well as high (AATs).
StepActionValuesYesNo
IMPORTANT: The ambient air temperature (AAT) must be at least 16°C (60°F). Do not induce additional air flow across the front of the vehicle during the test. If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.
1Park the vehicle inside or in the shade. Open the windows in order to ventilate the interior of the vehicle. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes. Turn OFF the ignition. Install the J 43600 ACR 2000 Air Conditioning Service Center. See Special Tools . Record the ambient air temperature (AAT) displayed on the J 43600 . See Special Tools . Record readings of the low and high side STATIC pressures. Are both the low and high side pressures within the specified value?Above 16°C (60°F) - 345 kPa (50 psi) Above 24°C (75°F) - 483 kPa (70 psi) Above 33°C (90°F) - 690 kPa (100 psi)Go to Step 2Go to Leak Testing
2IMPORTANT: Record the relative humidity and the AAT AT THE TIME OF THE TEST. Close the vehicle doors and windows. Open the driver door window 12.7-15.2 cm (5-6 in). Select the following HVAC control setting: The A/C is ON. The coldest temperature setting The maximum blower speed Recirculation mode The instrument panel (I/P) outlet mode All I/P outlets are OPEN Install the temperature probes of the J 43600 in the left and right center panel air outlets. See Special Tools . Apply the parking brake. Place the transmission in PARK. Start the engine. Operate the A/C system for 5 minutes. Inspect A/C components for the following conditions: Abnormal frost areas Unusual noises IMPORTANT: When performing this step it is necessary to press the RESET button on the J 43600 before pressing the PRINT button. See Special Tools . Print the following information: The panel outlet air temperatures The low-side pressure The high-side pressure Compare the low and high side pressures and the panel output temperatures to the A/C performance table below. Does all the data recorded fall within the specified ranges of the A/C performance table?Go to Step 8Go to Step 3
3If the pressures and temperatures recorded do not fall within the specified ranges: Continue to operate the A/C system for an additional 5 minutes. Record the pressures and temperatures again. Compare the low and high side pressures and the panel output temperature to the A/C performance table. Does all the data recorded fall within the specified ranges of the A/C performance table?Go to Step 8Go to Step 4
4Do the high and low side pressures fall within the specified ranges, but the panel outlet temperatures do not?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone AGo to Step 5
5Is the low side pressure greater than the specified range, but the high side pressure is within or less than the specified range?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone BGo to Step 6
6Are the low and high side pressures both greater than the specified ranges?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone CGo to Step 7
7Is the high side pressure greater than the specified range, but the low side pressure is within or less than the specified range?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone DGo to Step 8
8Operate the system in order to verify the test results. Did you find the same results?System OKGo to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or to Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
IMPORTANT
The ambient air temperature (AAT) must be at least 16°C (60°F). Do not induce additional air flow across the front of the vehicle during the test. If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.
IMPORTANT
Record the relative humidity and the AAT AT THE TIME OF THE TEST.
IMPORTANT
When performing this step it is necessary to press the RESET button on the J 43600 before pressing the PRINT button. See Special Tools .

Air Conditioning (A/C) System Performance Test (LY7)

Scheme 12

Scheme 12: A/C System Pressure - Zone Classification
Scheme 12: A/C System Pressure - Zone Classification
Ambient Air TemperatureRelative HumidityService Port PressureMaximum Left Center Discharge Air Temperature
Low SideHigh Side
13-18°C (55-65°F)0-100%158-254 kPa (23-37 psi)881-1288 kPa (128-187 psi)18°C (64°F)
19-24°C (65-75°F)Below 40%151-227 kPa (22-33 psi)923-1329 kPa (134-193 psi)15°C (59°F)
Above 40%172-275 kPa (25-40 psi)1047-1460 kPa (152-212 psi)20°C (68°F)
25-29°C (75-85°F)Below 35%158-241 kPa (25-35 psi)1157-1481 kPa (168-215 psi)18°C (63°F)
35-50%186-254 kPa (27-37 psi)1233-1522 kPa (179-221 psi)19°C (66°F)
Above 50%199-282 kPa (29-41 psi)1281-1598 kPa (186-232 psi)23°C (72°F)
30-35°C (85-95°F)Below 30%179-254 kPa (26-37 psi)1336-1667 kPa (194-242 psi)20°C (68°F)
30-50%192-268 kPa (28-39 psi)1378-1708 kPa (200-248 psi)22°C (70°F)
Above 50%213-296 kPa (31-43 psi)1440-1770 kPa (209-256 psi)24°C (75°F)
36-41°C (95-105°F)Below 20%199-268 kPa (29-39 psi)1550-1867 kPa (225-271 psi)23°C (73°F)
20-40%206-282 kPa (30-41 psi)1570-1887 kPa (228-274 psi)24°C (75°F)
Above 40%220-296 kPa (32-43 psi)1612-1908 kPa (234-277 psi)25°C (77°F)
42-46°C (105-115°F)Below 20%220-289 kPa (32-42 psi)1777-2053 kPa (258-298 psi)25°C (77°F)
Above 20%227-296 kPa (33-43 psi)1791-2060 kPa (260-299 psi)27°C (79°F)
47-49°C (115-120°F)Below 30%248-310 kPa (36-45 psi)1970-2218 kPa (286-322 psi)28°C (82°F)

A/C Performance Table

This test measures the operating efficiency of the A/C system under the following conditions

  1. The current ambient air temperature (AAT)
  2. The current relative humidity
  3. The high side pressure of the A/C system
  4. The low side pressure of the A/C system
  5. The temperature of the air being discharged into the passenger compartment

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

  1. 1: This step determines if the A/C system has at least the minimum refrigerant charge required to operate the system without damage.
  2. 2: This step measures the performance of the A/C system.
  3. 3: This step is to allow for vehicle variations as well as high (AATs).
StepActionValuesYesNo
IMPORTANT: The ambient air temperature (AAT) must be at least 16°C (60°F). Do not induce additional air flow across the front of the vehicle during the test. If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.
1Park the vehicle inside or in the shade. Open the windows in order to ventilate the interior of the vehicle. If the A/C system was operating, allow the A/C system to equalize for about 2 minutes. Turn OFF the ignition. Install the J 43600 ACR 2000 Air Conditioning Service Center. See Special Tools . Record the ambient air temperature (AAT) displayed on the J 43600 . See Special Tools . Record readings of the low and high side STATIC pressures. Are both the low and high side pressures within the specified value?Above 16°C (60°F) - 345 kPa (50 psi) Above 24°C (75°F) - 483 kPa (70 psi) Above 33°C (90°F) - 690 kPa (100 psi)Go to Step 2Go to Leak Testing
2IMPORTANT: Record the relative humidity and the AAT AT THE TIME OF THE TEST. Close the vehicle doors and windows. Open the driver door window 12.7-15.2 cm (5-6 in). Select the following HVAC control setting: The A/C is ON. The coldest temperature setting The maximum blower speed Recirculation mode The instrument panel (I/P) outlet mode All I/P outlets are OPEN Install the temperature probes of the J 43600 in the left and right center panel air outlets. See Special Tools . Apply the parking brake. Place the transmission in PARK. Start the engine. Operate the A/C system for 5 minutes. Inspect A/C components for the following conditions: Abnormal frost areas Unusual noises IMPORTANT: When performing this step it is necessary to press the RESET button on the J 43600 before pressing the PRINT button. See Special Tools . Print the following information: The panel outlet air temperatures The low-side pressure The high-side pressure Compare the low and high side pressures and the panel output temperatures to the A/C performance table below. Does all the data recorded fall within the specified ranges of the A/C performance table?Go to Step 8Go to Step 3
3If the pressures and temperatures recorded do not fall within the specified ranges: Continue to operate the A/C system for an additional 5 minutes. Record the pressures and temperatures again. Compare the low and high side pressures and the panel output temperature to the A/C performance table. Does all the data recorded fall within the specified ranges of the A/C performance table?Go to Step 8Go to Step 4
4Do the high and low side pressures fall within the specified ranges, but the panel outlet temperatures do not?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone AGo to Step 5
5Is the low side pressure greater than the specified range, but the high side pressure is within or less than the specified range?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone BGo to Step 6
6Are the low and high side pressures both greater than the specified ranges?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone CGo to Step 7
7Is the high side pressure greater than the specified range, but the low side pressure is within or less than the specified range?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone DGo to Step 8
8Operate the system in order to verify the test results. Did you find the same results?System OKGo to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or to Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
IMPORTANT
The ambient air temperature (AAT) must be at least 16°C (60°F). Do not induce additional air flow across the front of the vehicle during the test. If you were sent here from a DTC diagnostic table, clear the DTC upon completion of this test.
IMPORTANT
Record the relative humidity and the AAT AT THE TIME OF THE TEST.
IMPORTANT
When performing this step it is necessary to press the RESET button on the J 43600 before pressing the PRINT button. See Special Tools .

Air Conditioning (A/C) System Performance Test (L26)

Scheme 13

Scheme 13: A/C System Pressure - Zone Classification
Scheme 13: A/C System Pressure - Zone Classification
Ambient Air TemperatureRelative HumidityService Port PressureMaximum Left Center Discharge Air Temperature
Low SideHigh Side
13-18°C (55-65°F)0-100%151-179 kPa (22-26 psi)868-1267 kPa (126-184 psi)8°C (46°F)
19-24°C (65-75°F)Below 40%151-186 kPa (22-27 psi)888-1281 kPa (129-186 psi)8°C (46°F)
Above 40%151-206 kPa (22-30 psi)1019-1419 kPa (148-206 psi)10°C (50°F)
25-29°C (76-85°F)Below 35%151-192 kPa (22-28 psi)1109-1412 kPa (161-205 psi)8°C (46°F)
35-50%151-199 kPa (22-29 psi)1178-1460 kPa (171-212 psi)10°C (50°F)
Above 50%151-220 kPa (22-32 psi)1240-1550 kPa (180-225 psi)13°C (54°F)
30-35°C (85-95°F)Below 30%151-206 kPa (22-30 psi)1267-1591 kPa (184-231 psi)10°C (50°F)
30-50%151-220 kPa (22-32 psi)1322-1639 kPa (192-238 psi)13°C (54°F)
Above 50%165-241 kPa (24-35 psi)1378-1708 kPa (200-248 psi)14°C (57°F)
36-41°C (95-105°F)Below 20%151-213 kPa (22-31 psi)1460-1756 kPa (212-255 psi)12°C (52°F)
20-40%158-227 kPa (23-33 psi)1481-1791 kPa (215-260 psi)13°C (55°F)
Above 40%172-241 kPa (25-35 psi)1529-1832 kPa (222-266 psi)14°C (57°F)
42-46°C (105-115°F)Below 20%172-227 kPa (25-33 psi)1660-1922 kPa (241-279 psi)13°C (54°F)
Above 20%179-241 kPa (26-35 psi)1681-1942 kPa (244-282 psi)14°C (57°F)
47-49°C (115-120°F)Below 30%186-248 kPa (27-36 psi)1839-2087 kPa (267-303 psi)15°C (59°F)

A/C Performance Table

Air Conditioning (A/C) Diagnostics - Pressure Zone A

StepActionValueYesNo
DEFINITION: The high and low side pressures may be normal or slightly less than normal. Air Delivery Concern Slight Refrigerant Under Charge Refrigerant Contamination
1Were you sent here from the A/C System Performance Test?Go to Step 2Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
2Refer to the instrument panel outlet air temperatures recorded during the A/C system performance test. Does the discharge air temperature between the right and left center instrument panel outlets vary by more than 1-2°C (2-3°F)?Go to Step 7Go to Step 3
3Did the customer mention that the A/C system output temperatures are good at first, but then turn warm during extended drives?Go to Step 4Go to Step 5
4Increase engine speed to 2,000 RPM. During extended operation of the A/C system, does the low side pressure decrease, possibly accompanied by heavy frost on the liquid line between the expansion device and the evaporator?Go to Air Conditioning (A/C) Diagnostics - Pressure Zone DGo to Step 5
5Refer to the pressures recorded during the A/C system performance test. Inspect for the following conditions: CAUTION: Refer to Moving Parts and Hot Surfaces Caution . The high side pressure is slightly greater than the specified pressure ranges but still within Zone A on the A/C Pressure-Zone Classification Chart in the A/C System Performance Test. Refer to Air Conditioning (A/C) System Performance Test (LY7) Air Conditioning (A/C) System Performance Test (L26) . The discharge line is hot. The suction line is cool. Do the listed conditions exist?Go to Step 7Go to Step 6
6Refer to the pressures recorded during the A/C system performance test. Inspect for the following conditions: The low side pressure is slightly lower than the specified pressure ranges but still within Zone A on the A/C Pressure-Zone Classification Chart in the A/C System Performance Test. Refer to Air Conditioning (A/C) System Performance Test (LY7) Air Conditioning (A/C) System Performance Test (L26) . The discharge line is warm-to-hot. The suction line is cool-to-warm. Do the listed conditions exist?Go to Step 8Go to Too Hot in Vehicle for the manual system or Go to Too Hot in Vehicle for the automatic system
7The A/C system may be undercharged. Leak test A/C system. Refer to Leak Testing . Recharge the A/C system to specifications. Refer to Refrigerant Recovery and Recharging . Is the action complete?Go to Step 13
8The A/C system may be contaminated. View the information screen on the J 43600 for detection of foreign gases in the A/C system. See Special Tools . Do foreign gases exist?Go to Step 9Go to Step 10
9Evacuate the A/C system to a scavenging tank. Refer to Refrigerant Recovery and Recharging . Recharge the A/C system to specifications. Is the action complete?Go to Step 13
10The A/C system may contain too much moisture or air. Evacuate and recharge the A/C system to specifications. Refer to Refrigerant Recovery and Recharging . Operate the A/C system and inspect the instrument panel outlet air temperatures. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Are the instrument panel outlet air temperatures within the specified ranges of the A/C Performance Test Table?Go to Step 14Go to Step 11
11The A/C system may contain too much refrigerant oil. IMPORTANT: Review the vehicle's A/C repair history. If the vehicle history shows multiple A/C repairs and is suspected of improper PAG oil balancing in the previous repairs, perform the following procedure: Drain all of the PAG oil drain bottle on the ACR 2000. Flush the A/C system. Refer to Flushing . Was more than the total system capacity of refrigerant oil recovered from the ACR 2000 oil drain bottle?150 ml (5 oz.)Go to Step 12Go to Step 13
12Add the specified amount of refrigerant oil. Refer to Refrigerant System Capacities . Recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Are the actions complete?Go to Step 13
13Record the low and high side pressures and the instrument panel outlet air temperature. Compare the instrument panel outlet air temperatures to those listed in the A/C System Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Are the high and low side pressures and the instrument panel outlet air temperatures within specifications?Go to Step 14
14Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Symptoms - HVAC Systems - Manual for the manual system or Go to Symptoms - HVAC Systems - Automatic for the automatic system
IMPORTANT
Review the vehicle's A/C repair history.

Air Conditioning (A/C) Diagnostics - Pressure Zone A

Air Conditioning (A/C) Diagnostics - Pressure Zone B

StepActionYesNo
DEFINITION: The low side pressure is higher than normal and the high side pressure is lower than normal. Malfunctioning A/C Compressor Refrigerant Under Charge
1Were you sent here from the A/C System Performance Test?Go to Step 2Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
2After continued operation of the A/C system, do the low and the high side pressures equalize or become static?Go to Step 5Go to Step 3
3Refer to the pressures recorded during the A/C System Performance Test. Inspect for the following conditions: CAUTION: Refer to Moving Parts and Hot Surfaces Caution . The low side pressure is equal to or greater than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (LY7) Air Conditioning (A/C) System Performance Test (L26) . The high side pressure is less than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (LY7) Air Conditioning (A/C) System Performance Test (L26) . The low side refrigerant line at the compressor feels cool-to-warm. The high side refrigerant line at the compressor feels warm-to-hot. Do the listed conditions exist?Go to Step 5Go to Step 4
4Refer to the pressures recorded during the A/C System Performance Test. Inspect for the following conditions: CAUTION: Refer to Moving Parts and Hot Surfaces Caution . The low side pressure is greater than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (LY7) Air Conditioning (A/C) System Performance Test (L26) . The high side pressure is less than the specified pressure range of the A/C Performance Table. Refer to Air Conditioning (A/C) System Performance Test (LY7) Air Conditioning (A/C) System Performance Test (L26) . The low side refrigerant line at the compressor feels warm. The high side refrigerant line at the compressor feels warm-to-hot. Do the listed conditions exist?Go to Step 5Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
5The A/C system has a low refrigerant charge. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the action complete?Go to Step 6
6After you perform the repairs, record the following: The low and the high side pressures The instrument panel outlet air temperature Compare the pressures and the temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Are the readings within the specified ranges found on the A/C Performance Chart?Go to Step 13Go to Step 7
7The A/C compressor is malfunctioning. Remove the expansion device and inspect for contamination. Refer to Thermal Expansion Valve Replacement . Did you find metal flakes on the expansion device?Go to Step 9Go to Step 8
8Inspect the expansion device for a brown, powdery residue indicating desiccant in the A/C system. Is a brown, powdery residue present?Go to Step 11Go to Step 12
9Remove the compressor hose from the compressor. Refer to Compressor Hose Assembly Replacement (L26) or Compressor Hose Assembly Replacement (LY7) . Inspect for metal flake contamination at the line connections and the compressor ports. Is metal flake contamination present?Go to Step 10Go to Step 12
10Replace the A/C compressor. Refer to Compressor Replacement (L26) or Compressor Replacement (LY7) . Replace the thermal expansion valve. Refer to Thermal Expansion Valve Replacement . Replace the A/C refrigerant filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the action complete?Go to Step 13
11Flush the A/C system. Refer to Flushing . Replace the thermal expansion valve. Refer to Thermal Expansion Valve Replacement . Replace the A/C compressor. Refer to Compressor Replacement (L26) or Compressor Replacement (LY7) . Replace the A/C refrigerant filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Replace the condenser. Refer to Condenser Replacement . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the action complete?Go to Step 13
12Replace the A/C compressor. Refer to Compressor Replacement (L26) or Compressor Replacement (LY7) . Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the action complete?Go to Step 13
13Operate the system in order to verify the repair Did you find and correct the condition?System OKGo to Symptoms - HVAC Systems - Manual for the manual system or Go to Symptoms - HVAC Systems - Automatic for the automatic system

Air Conditioning (A/C) Diagnostics - Pressure Zone B

Air Conditioning (A/C) Diagnostics - Pressure Zone C

StepActionYesNo
DEFINITION: The low and the high side pressures are both higher than normal. Restricted Condenser Air Flow Cooling Fan Malfunction Expansion Device Malfunction
1Were you sent here from the A/C System Performance Test?Go to Step 2Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
2Start the engine. Turn ON the A/C. Inspect for proper cooling fan operation. Refer to Cooling System Description and Operation in Engine Cooling. Are the cooling fans ON and operating properly?Go to Step 3Go to Step 5
3Visually inspect for the following conditions: Damaged condenser cooling fins Missing or misaligned air baffles Restricted air flow Do any of these conditions exist?Go to Step 4Go to Step 6
4Repair the air flow restriction. Is the action complete?Go to Step 9
5Repair the fault to the cooling fan operation. Refer to Cooling Fan Inoperative in Engine Cooling. Is the repair complete?Go to Step 9
6CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Feel the liquid line on both sides of the expansion device.Are the temperatures on both sides of the expansion device similar?Go to Step 7Go to Step 8
7Replace the damaged or faulty thermal expansion valve. Refer to Thermal Expansion Valve Replacement . Is the action complete?Go to Step 9
8Air is in the refrigerant system or the system is overcharged. Refer to the view screen on J 43600 ARC Air Conditioning Service Center for foreign gas content in the refrigerant. See Special Tools . Recover and recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Is the action complete?Go to Step 9
9Record the low and high side pressures and the instrument panel outlet air temperature after you have performed the repairs. Compare the pressures and the instrument panel outlet air temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Are the readings within the specified ranges listed in the A/C Performance Chart?Go to Step 10Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
10Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
CAUTION
Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices.

Air Conditioning (A/C) Diagnostics - Pressure Zone C

Air Conditioning (A/C) Diagnostics - Pressure Zone D

StepActionYesNo
DEFINITION: The low side pressure is lower than normal and the high side pressure is higher than normal. A restriction in the A/C system. Debris in the system.
1Were you sent here from the A/C System Performance Test?Go to Step 2Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
2CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Feel the liquid line before the expansion device.Is the liquid line cold before the expansion device?Go to Step 3Go to Step 8
3Feel along the surfaces of the following high side components: The compressor discharge hose The condenser The liquid line between the condenser and the expansion device Did you detect an abrupt drop in temperature along the surfaces of any of the listed components?Go to Step 7Go to Step 4
4Feel the liquid line at the expansion device location for extreme cold, possibly accompanied by heavy frost. Feel along the liquid line beyond the expansion device location for warm temperature. Is the liquid line extremely cold at the expansion device location and warm beyond the expansion device location?Go to Step 11Go to Step 5
5Feel along the surfaces of the following low side components: The evaporator inlet tube between the expansion device and the evaporator core The evaporator outlet tube between the evaporator core and the compressor suction hose The compressor suction hose Did you feel an abrupt temperature change along the surfaces of any of the listed components?Go to Step 7Go to Step 6
6Feel along the surfaces of the low and the high side components. The evaporator inlet tube between the expansion device and the evaporator core The evaporator outlet tube and the compressor The compressor suction hose The compressor discharge hose The condenser The evaporator inlet tube between the condenser and the expansion device Are the temperatures of these components only mildly warm?Go to Step 14Go to Step 8
7Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Remove the restriction from the component, or replace the component which produced an abrupt temperature drop. Is the action complete?Go to Step 9
8Recover the refrigerant and evacuate the system. Refer to Refrigerant Recovery and Recharging . Record the weight of the recovered refrigerant. Compare the weight of the recovered refrigerant with the system capacity. Refer to Refrigerant System Capacities . Is the weight of the recovered refrigerant charge greater than 75 percent of the total system capacity?Go to Step 9Go to Step 10
9Recharge the A/C System. Refer to Refrigerant Recovery and Recharging . Is the cooling performance improved?Go to Step 21Go to Step 10
10Leak test the system. Refer to Leak Testing . Repair any leaks. Is the action complete?Go to Step 21
11The expansion device is restricted. Replace the expansion device. Refer to Thermal Expansion Valve Replacement . If the expansion device was restricted, note the type of debris present. Are metal flakes present?Go to Step 12Go to Step 13
12Remove the compressor hose assembly from the vehicle. Refer to Compressor Hose Assembly Replacement (L26) or Compressor Hose Assembly Replacement (LY7) . Inspect the hose for debris by blowing shop air through one end of the hose while covering the other end with a shop towel. Observe the amount of debris collected in the shop towel. Did a large amount of debris collect in the shop towel?Go to Step 18Go to Step 20
13If the expansion device was restricted with a brown or black residue, perform the following procedure: Flush the A/C System. Refer to Flushing . Replace the A/C refrigerant filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Replace the condenser. Refer to Condenser Replacement . Are the actions complete?Go to Step 21
14Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Disconnect the compressor hose from the compressor. Refer to Compressor Hose Assembly Replacement (L26) or Compressor Hose Assembly Replacement (LY7) . Inspect for the presence of debris in the compressor suction port. Is debris present in the compressor suction port?Go to Step 15Go to Step 19
15Remove the debris from the suction port. Inspect the expansion device for damage or debris. Refer to Thermal Expansion Valve Replacement . Did you find evidence of damage or debris?Go to Step 17Go to Step 16
16If the expansion device does not show any signs of damage or debris, perform the following procedure: Remove the compressor hose assembly from the vehicle. Refer to Compressor Hose Assembly Replacement (L26) or Compressor Hose Assembly Replacement (LY7) . Inspect the hose for debris by blowing shop air through one end of the hose while covering the other end with a shop towel. Observe the amount of debris collected in the shop towel. Did a large amount of debris collect in the shop towel?Go to Step 18Go to Step 19
17Replace the expansion device. Refer to Thermal Expansion Valve Replacement . If the expansion device was restricted, observe the type of debris present. Are metal flakes present?Go to Step 12Go to Step 13
18If a large amount of debris was collected in the shop towel from the suction hose, perform the following procedure: Replace the A/C condenser. Refer to Condenser Replacement . Replace the A/C refrigerant filter. Refer to Air Conditioning (A/C) Refrigerant Filter Replacement . Is the action complete?Go to Step 19
19Install the compressor hose assembly. Refer to Compressor Hose Assembly Replacement (L26) or Compressor Hose Assembly Replacement (LY7) . Is the action complete?Go to Step 21
20Install the compressor hose assembly. Refer to Compressor Hose Assembly Replacement (L26) or Compressor Hose Assembly Replacement (LY7) . Recharge the A/C system. Refer to Refrigerant Recovery and Recharging . Are the actions complete?Go to Step 21
21Record the low and the high side pressures and the instrument panel outlet air temperature after you perform the repairs. Compare the pressures and the instrument panel outlet air temperature to those listed in the A/C Performance Chart. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Are the readings within the specified ranges as shown on the A/C Performance Chart?Go to Step 22Go to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26)
22Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or to Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
CAUTION
Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices.

Air Conditioning (A/C) Diagnostics - Pressure Zone D

Heating Performance Diagnostic

StepActionYesNo
DEFINITION: Heating system performance
1Were you sent here from Symptoms or another diagnostic table?Go to Step 2Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or to Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
2Start the engine. Allow the engine to idle. Does the engine reach normal operating temperature?Go to Step 3Go to Step 9
3CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Allow the engine to idle. Select the FLOOR mode. Select the minimum blower speed. Select the warmest temperature setting. Feel the temperature of the inlet and outlet heater hoses at the heater core. Does the inlet heater hose feel warmer than the outlet heater hose?Go to Step 7Go to Step 4
4Install a thermometer into the center instrument panel (I/P) PANEL air outlet. Secure a thermometer to the heater core outlet heater hose. Select the PANEL mode. Select the maximum blower speed. Select the warmest temperature setting. Record the temperature at the following locations: The center I/P PANEL air outlet The heater core outlet heater hose Compare the recorded temperatures. Are the 2 temperature readings about equal?Go to Step 5Go to Step 6
5Inspect and repair the following areas of the vehicle for cold air leaks: The cowl The recirculation door The HVAC module case Perform the necessary repairs. Are the repairs complete?Go to Step 10
6Inspect the temperature door operation. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information. Perform any necessary repairs. Are the repairs complete?Go to Step 10
7Turn OFF the engine. Backflush the heater core. Start the engine. Select the FLOOR mode. Select the minimum blower speed. Select the warmest temperature setting. Feel the temperature of the inlet and outlet heater hoses at the heater core. Does the inlet heater hose feel warmer than the outlet heater hose?Go to Step 8Go to Step 10
8Replace the heater core. Refer to Heater Core Replacement . Is the repair complete?Go to Step 10
9Repair the low engine temperature concern. Refer to Engine Fails To Reach Normal Operating Temperature (LY7) in Engine Cooling. Is the repair complete?Go to Step 10
10Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2
CAUTION
Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices.

Heating Performance Diagnostic

Defrosting Insufficient

StepActionYesNo
DEFINITION: Time required to defrost the windshield is longer than usual.
1Were you sent here from Symptoms or another diagnostic table?Go to Step 2Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or to Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
2Start the engine. Select the DEFROST mode. Select the maximum blower speed. Does sufficient air flow from the defroster outlets?Go to Step 3Go to Step 10
3Measure the engine operating temperature. Does the engine reach normal operating temperature?Go to Step 4Go to Step 8
4Select the minimum blower speed. Select the warmest temperature setting. CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Feel the temperature of the inlet and outlet heater hoses at the heater core. Does the inlet heater hose feel warmer than the outlet heater hose?Go to Step 11Go to Step 5
5Test the operation of the A/C compressor clutch. Does the A/C compressor clutch engage?Go to Step 7Go to Step 6
6Repair the A/C compressor clutch. Refer to HVAC Compressor Clutch Does Not Engage in HVAC Systems-Manual. Is the repair complete?Go to Step 14
7Perform the A/C system performance test. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Is the A/C system operating within the specifications?Go to Step 9Go to Step 12
8Repair the low engine temperature concern. Refer to Engine Fails To Reach Normal Operating Temperature (LY7) in Engine Cooling. Is the repair complete?Go to Step 14
9Inspect for correct operation of the recirculation door. Is the recirculation door operating correctly?Go to Step 14Go to Step 13
10Repair the air delivery concern. Refer to Air Delivery Improper in HVAC Systems - Manual. Is the repair complete?Go to Step 14
11Repair the heating concern. Refer to Heating Performance Diagnostic . Is the repair complete?Go to Step 14
12Repair the A/C performance concern. Refer to Air Conditioning (A/C) System Performance Test (LY7) or Air Conditioning (A/C) System Performance Test (L26) . Is the repair complete?Go to Step 14
13Repair the recirculation door concern. Is the repair complete?Go to Step 14
14Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2
CAUTION
Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices.

Defrosting Insufficient

Noise Diagnosis - Blower Motor

StepActionYesNo
DEFINITION: Noise originating from the blower motor.
1Were you sent here from Symptoms or another diagnostic table?Go to Step 2Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
2Inspect the air inlet grille for debris. Is debris present?Go to Step 8Go to Step 3
3Sit inside the vehicle. Close the vehicle doors and windows. Turn ON the ignition, with the engine OFF. Cycle the blower motor through all of the speeds in order to determine where and when the noise occurs. Did you hear a noise during the blower operation?Go to Step 4Go to Step 11
4Inspect for excessive vibration at each blower motor speed by feeling the blower case. Is excess vibration present?Go to Step 6Go to Step 5
5Listen to the blower motor at each blower speed. Is the blower motor making a squeaking or chirping noise?Go to Step 9Go to Step 11
6Remove the blower motor. Refer to Blower Motor Replacement . Inspect the blower motor impeller for deposits of foreign material. Inspect the blower motor for deposits of foreign material. Did you find any foreign material on the blower motor or blower motor impeller?Go to Step 8Go to Step 7
7Inspect the blower motor for the following conditions: Cracked blades A loose impeller retainer Improper impeller alignment Did you find any of these conditions?Go to Step 9Go to Step 10
8Remove the foreign material. Is the action complete?Go to Step 10
9Replace the blower motor. Refer to Blower Motor Replacement . Is the repair complete?Go to Step 11
10Install the blower motor. Refer to Blower Motor Replacement . Is the action complete?Go to Step 11
11Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2

Noise Diagnosis - Blower Motor

Noise Diagnosis - Air Conditioning (A/C) System

StepActionYesNo
DEFINITION: Noise originating from the A/C compressor, drive belt or the A/C lines.
1Were you sent here from Symptoms or another diagnostic table?Go to Step 2Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
2A/C system noises can be generally categorized into 3 areas: Screeching, squealing or chirping noises Moaning noises Vibration/rattle noises Start the engine. Ensure that the A/C is ON. Is a screeching or squealing noise heard when the A/C is engaged?Go to Step 3Go to Step 9
3With the engine OFF, inspect the drive belt for excessive wear. Refer to Drive Belt Excessive Wear Diagnosis in Engine Mechanical - 3.8L or Drive Belt Excessive Wear Diagnosis in Engine Mechanical - 3.6L (LY7). Is the drive belt excessively worn?Go to Step 18Go to Step 4
4Inspect the drive belt tension. Refer to Drive Belt Tensioner Diagnosis in Engine Mechanical - 3.8L or Drive Belt Tensioner Diagnosis in Engine Mechanical - 3.6L (LY7). Is the drive belt tension correct?Go to Step 5Go to Step 19
5Inspect the drive belt for excessive oil coverage. Is the drive belt covered with oil?Go to Step 17Go to Step 6
6Start the engine. Ensure that the A/C is ON. Inspect the compressor and the clutch. Is the A/C compressor locked up?Go to Step 24Go to Step 7
7Is the A/C compressor clutch slipping?Go to Step 23Go to Step 8
8CAUTION: Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices. Using a stethoscope, listen to the A/C compressor for any abnormal noise.Is the compressor causing an abnormal noise?Go to Step 15Go to Step 10
9Does a moaning noise exist when the A/C clutch is engaged?Go to Step 10Go to Step 12
10Listen to the A/C compressor components and mounting for noise concerns using a stethoscope. Are any of these components loose, damaged or excessively worn?Go to Step 20Go to Step 11
11Idle the engine. Engage the A/C compressor clutch. Using a stethoscope, move around the entire refrigerant plumbing system. Listen for any abnormal noises caused by a component of the A/C system touching another component. Are any of the A/C components grounding out and causing a vibration noise?Go to Step 22Go to Step 13
12Does a vibration or rattle noise exist when the A/C clutch is engaged?Go to Step 13Go to Step 14
13Does the noise stop when the A/C clutch is disengaged?Go to Step 15Go to Step 25
14Idle the engine in PARK with the A/C compressor clutch engaged. Using a stethoscope, move around the entire A/C system testing for any abnormal noises caused by a component. Do any of the A/C components cause an abnormal noise?Go to Step 21Go to Step 25
15Verify that the A/C system is properly charged. Refer to Refrigerant System Capacities . Is the A/C system properly charged?Go to Step 26Go to Step 16
16Recharge the A/C system to specification. Refer to Refrigerant Recovery and Recharging . Is the abnormal compressor noise still present?Go to Step 24Go to Step 26
17Repair the oil leak. Refer to the appropriate repair procedure in Engine Mechanical - 3.8L or in Engine Mechanical - 3.6L (LY7). Is the action complete?Go to Step 26
18Replace the drive belt. Refer to Drive Belt Replacement (L26) in Engine Mechanical - 3.8L or Drive Belt Replacement in Engine Mechanical - 3.6L (LY7). Is the action complete?Go to Step 26
19Replace the drive belt tensioner. Refer to Drive Belt Tensioner Replacement in Engine Mechanical - 3.8L or Drive Belt Tensioner Replacement in Engine Mechanical - 3.6L (LY7). Is the action complete?Go to Step 26
20Repair or replace the A/C compressor mounting component. Is the action complete?Go to Step 26
21Repair or replace the component which is causing the moaning concern as needed. Is the action complete?Go to Step 26
22Correctly route or insulate the A/C component. Is the action complete?Go to Step 26
23Replace the A/C compressor clutch. Refer to Compressor Clutch Assembly Replacement . Is the action complete?Go to Step 26
24Replace the A/C compressor. Refer to Compressor Replacement (L26) or Compressor Replacement (LY7) . Is the action complete?Go to Step 26
25The concern may be caused by an engine related component. Refer to Vibration Analysis - Engine in Vibration Diagnosis and Correction. Did you find and correct the condition?Go to Step 26
26Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2
CAUTION
Refer to Moving Parts and Hot Surfaces Caution in Cautions and Notices.

Noise Diagnosis - Air Conditioning (A/C) System

Noise Diagnosis - HVAC Module

StepActionYesNo
DEFINITION: Noise originating from the HVAC module.
1Were you sent here from Symptoms or another diagnostic table?Go to Step 2Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
2Start the engine. Cycle through all of the following: Blower motor speeds HVAC modes Temperature control settings Determine the type of noise: Scrape, pop Tick/click, chirp or groaning Air rush/whistle Is a scrape or pop noise evident when selecting modes or temperature settings?Go to Step 6Go to Step 3
3Is a tick/click, chirping, groaning or scraping noise present, but decreases as blower motor speed is decreased?Go to Step 6Go to Step 4
4Is an air rush/whistle noise evident in all modes, but not all temperature settings?Go to Step 6Go to Step 5
5Is an air rush/whistle noise evident only in defrost or floor mode?Go to Step 6Go to Step 1
6Remove the instrument panel (I/P) trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) in Instrument Panel, Gages, and Console. Is the action complete?Go to Step 7
7Inspect the mode valve assembly for proper operation. Inspect the ducts for obstructions or foreign materials. Were any of these conditions found?Go to Step 10Go to Step 8
8Inspect the mode valve assembly, temperature door, and seals for warping or cracking. Are the doors in normal condition?Go to Step 11Go to Step 9
9Replace the appropriate door, mode valve assembly, or seals. Is the repair complete?Go to Step 11
10Remove any obstructions or foreign material found. Is the action complete?Go to Step 11
11Install the I/P trim pad. Refer to Trim Pad Replacement - Instrument Panel (I/P) in Instrument Panel, Gages, and Console. Is the action complete?Go to Step 12
12Operate the system to verify the repair. Did you find and correct the condition?System OKGo to Step 2

Noise Diagnosis - HVAC Module

Odor Diagnosis

StepActionYesNo
DEFINITION: Odor originating or noticed through the HVAC system.
1Were you sent here from Symptoms or another diagnostic table?Go to Step 2Go to Symptoms - HVAC Systems - Manual in HVAC Systems - Manual or Symptoms - HVAC Systems - Automatic in HVAC Systems - Automatic
2Sit inside the vehicle. Close all of the doors and windows. Start the engine. Allow the engine idle at normal operating temperature. Select the maximum blower speed. Select the PANEL air outlet mode. Select the coldest temperature setting. Cycle through all of the blower speeds, modes, and temperatures to define what type of odor is present. Musty smell Coolant smell Oil smell Does the odor have a musty smell?Go to Step 3Go to Step 8
3Inspect the HVAC air inlet grille for debris. Is debris present?Go to Step 4Go to Step 5
4Remove any debris. Is the action complete?Go to Step 15
5Inspect for wet carpeting. Is the carpet wet?Go to Step 6Go to Step 14
6Inspect for the following conditions: Water leaks around the windshield Blockage of the HVAC module drain Leaks around the door seals Is a leak present?Go to Step 7Go to Step 14
7Repair the leak, as necessary. Is the action complete?Go to Step 15
8Does the odor have a coolant smell?Go to Step 9Go to Step 12
9Inspect the cooling system for leaks. Refer to Loss of Coolant in Engine Cooling. Is a leak present?Go to Step 10Go to Step 12
10Inspect for coolant leaking inside the vehicle or for a film build-up on the windshield. Is the condition present?Go to Step 11Go to Step 15
11Replace the heater core. Refer to Heater Core Replacement . Is the action complete?Go to Step 15
12Does the odor have an oily smell?Go to Step 13Go to Step 15
13Inspect the engine compartment for any leaks. Refer to the following procedures: Oil Leak Diagnosis in Engine Mechanical - 3.6L (LY7) Oil Leak Diagnosis in Engine Mechanical - 3.8L Fluid Leak Diagnosis in Automatic Transmission - 4T65-E Power Steering Fluid Leaks in Power Steering System Repair any oil leaks. Is the action complete?Go to Step 15
14A musty odor can be caused by mold or mildew build-up on the evaporator, the heater core, or the inside of the HVAC module. Refer to Odor Correction . Is the action complete?Go to Step 15
15Operate the system in order to verify the repair. Did you find and correct the condition?System OKGo to Step 2

Odor Diagnosis

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 mirocbial 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 that 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 maximum 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. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  2. J 45037 A/C Oil Injector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
CAUTIONAvoid breathing the A/C Refrigerant 134a (R-134a) and the lubricant vapor or the mist. Exposure may irritate the eyes, nose, and throat. Work in a well ventilated area. In order to remove R-134a from the A/C system, use service equipment that is certified to meet the requirements of SAE J 2210 (R-134a recycling equipment). If an accidental system discharge occurs, ventilate the work area before continuing service. Additional health and safety information may be obtained from the refrigerant and lubricant manufacturers.
CAUTIONFor personal protection, goggles and gloves should be worn and a clean cloth wrapped around fittings, valves, and connections when doing work that includes opening the refrigerant system. If R-134a comes in contact with any part of the body severe frostbite and personal injury can result. The exposed area should be flushed immediately with cold water and prompt medical help should be obtained.

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. See Special Tools . 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. See Special Tools . Always recharge the A/C System with the proper amount of R-134a. Refer to 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 . See Special Tools . For the proper quantities of oil to add to the A/C refrigerant system, refer to Refrigerant System Capacities .

  1. J 43600 ACR 2000 Air Conditioning Service Center. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  2. J 45268 Flush Adapter Kit. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  3. J 41447 Leak Detection Dye. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  4. J 42220 Universal 12V Leak Detection Lamp. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Flushing Procedure

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

Flushing is intended to remove the following

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

Scheme 14

Scheme 14
Scheme 14
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the A/C refrigerant filter. Refer to «Air Conditioning (A/C) Refrigerant Filter Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  3. Remove the thermal expansion valve (TXV). Refer to «Thermal Expansion Valve Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  4. Install the stud for the J 45268 kit onto the J 45268-115. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  5. Install the J 45268-115 in place of the TXV.
  6. Install the TXV mounting bolts. Tighten: Tighten the bolts to 7 N.m (62 lb in).
  7. Connect the evaporator line to the J 45268-115.
  8. Install the TXV block fitting nut. Tighten: Tighten the bolts to 17 N.m (12.5 lb ft).
  9. Remove the A/C compressor. Refer to «Compressor Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) or «Compressor Replacement (LY7)»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  10. Install J 45268-10 to the A/C compressor hose assembly.
  11. Install the nut and bolt from the J 45268 kit to the J 45268-10 and compressor hose assembly. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) . Tighten: Tighten the bolts to 17 N.m (12.5 lb ft).
  12. Forward flow refrigerant flushing is recommended for contaminated refrigerant or PAG oil. Perform the following procedure: IMPORTANT: The filter inside 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. Install the port plugs J 45268-9 onto the J 45268-10. Install the fitting J 45268-7 onto the J 45268-10. Install the fitting J 45268-8 onto the J 45268-10. Connect J 45268-1 flush filter to the suction port of J 45268-7 flush adapter. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) . Connect the red hose from the J 43600 to the J 45268-8 flush adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  13. Reverse flow refrigerant flush is recommended for desiccant bag failure. Replace the A/C condenser when the A/C flush is complete and perform the following procedure: IMPORTANT: The filter inside 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. Install the port plugs J 45268-9 onto the J 45268-10. Install the fitting J 45268-7 onto the J 45268-10. Install the fitting J 45268-8 onto the J 45268-10. Connect J 45268-1 flush filter to the discharge port of J 45268-7 flush adapter. Connect the blue hose from J 43600 to the J 45268-1 flush filter adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) . Connect the red hose from J 43600 to the J 45268-8 flush adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  14. Flush the A/C system. Follow the instructions supplied with the J 43600 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  15. Disconnect the red hose on the J 43600 from the J 45268-10. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  16. Disconnect the blue hose on the J 43600 from the J 45268-1. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  17. Remove J 45268-1 from the J 45268-10.
  18. Remove the J 45268-10 from the A/C compressor hose assembly.
  19. If you will reinstall the removed A/C compressor, perform the following procedure: Remove the A/C compressor drain plug. Drain the PAG oil from the A/C compressor. Rotate the compressor input shaft to assist in draining the PAG oil from the compressor. Install the A/C compressor drain plug. Tighten: Tighten the drain plug to 16 N.m (12 lb ft). Add the total system capacity of PAG oil to the A/C compressor. Refer to «Refrigerant System Capacities»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__refrigerant-system-capacities) .
  20. 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 «Refrigerant System Capacities»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__refrigerant-system-capacities) . 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. Refer to «Refrigerant System Capacities»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__refrigerant-system-capacities) . Add the calculated amount to the compressor, as needed.
  21. Add one bottle of J 41447 directly to the A/C Compressor. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  22. Install the A/C compressor. Refer to «Compressor Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) or «Compressor Replacement (LY7)»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  23. Remove J 45268-115.
  24. Inspect the TXV for debris. Clean or replace as needed.
  25. Install the TXV. Refer to «Thermal Expansion Valve Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  26. Install the A/C refrigerant filter. Refer to «Air Conditioning (A/C) Refrigerant Filter Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  27. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  28. Leak test the fittings using J 42220 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Draining Procedure

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

Balancing Procedure

  1. The replacement compressor is shipped with the total system capacity of refrigerant oil.
  2. Before installing the compressor, the refrigerant oil may 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»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__refrigerant-system-capacities) . 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. See Special Tools .

Removal Procedure

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the drive belts. Refer to «Drive Belt Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) .
  3. Remove the splash shield from the right side of the engine. Refer to «Splash Shield Replacement - Engine»(/buick/lacrosse/i-2004-2009/remont/exterior-body-panels/#body-front-end) in Body Front End.
  4. Remove the hose nut from the A/C compressor.
  5. Remove the hose from the A/C compressor. IMPORTANT: Remove and discard all sealing washers.
  6. Disconnect the electrical connector from the A/C compressor.
  7. Loosen the rear mounting bolt from the A/C compressor.
  8. Remove the front mounting bolt from the A/C compressor.
  9. Remove the front mounting nut from the A/C compressor.
  10. Remove the A/C compressor.
  11. If replacing the compressor, balance the compressor oil. Refer to «Compressor Oil Balancing»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .

Installation Procedure

  1. Install the compressor drain plug. Tighten: Tighten the drain plug to 16 N.m (12 lb ft).
  2. Position the A/C compressor onto the front A/C compressor mounting stud and the rear A/C compressor mounting bolt.
  3. Install the A/C compressor front bolt. Tighten: Tighten the bolts to 50 N.m (36 lb ft).
  4. Install the A/C compressor front mounting nut. Tighten: Tighten the nut to 50 N.m (36 lb ft).
  5. Tighten the A/C compressor rear bolt. Tighten: Tighten the bolt to 50 N.m (36 lb ft).
  6. Install new sealing washers. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  7. Install the hose to the A/C compressor.
  8. Install the nut to the A/C compressor hose. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  9. Connect the electrical connector to the A/C compressor.
  10. Install the splash shield to the right side of the engine. Refer to «Splash Shield Replacement - Engine»(/buick/lacrosse/i-2004-2009/remont/exterior-body-panels/#body-front-end) in Body Front End.
  11. Install the drive belts. Refer to «Drive Belt Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) .
  12. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  13. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the drive belts. Refer to «Drive Belt Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) .
  3. Remove the splash shield from the right side of the engine. Refer to «Splash Shield Replacement - Engine»(/buick/lacrosse/i-2004-2009/remont/exterior-body-panels/#body-front-end) in Body Front End.
  4. Disconnect the electrical connector from the A/C compressor.
  5. Remove the compressor hose nut from the A/C compressor.
  6. Remove the compressor hose from the A/C compressor.
  7. Loosen the rear mounting bolt (1) from the A/C compressor.
  8. Remove the front mounting bolt (3) from the A/C compressor.
  9. Remove the front mounting nut (2) from the A/C compressor.
  10. Remove the A/C compressor.
  11. If replacing the compressor, balance the compressor oil. Refer to «Compressor Oil Balancing»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  1. Install the compressor drain plug. Tighten: Tighten the drain plug to 16 N.m (12 lb ft).
  2. Position the A/C compressor onto the front A/C compressor mounting stud and the rear A/C compressor mounting bolt (1).
  3. Install the A/C compressor front bolt (3). Tighten: Tighten the bolts to 50 N.m (36 lb ft).
  4. Install the A/C compressor front mounting nut (2). Tighten: Tighten the nut to 50 N.m (36 lb ft).
  5. Tighten the A/C compressor rear bolt. Tighten: Tighten the bolt to 50 N.m (36 lb ft).
  6. Install new sealing washers. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  7. Install the compressor hose to the A/C compressor.
  8. Install the nut to the A/C compressor hose. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  9. Connect the electrical connector to the A/C compressor.
  10. Install the splash shield to the right side of the engine. Refer to «Splash Shield Replacement - Engine»(/buick/lacrosse/i-2004-2009/remont/exterior-body-panels/#body-front-end) in Body Front End.
  11. Install the drive belts. Refer to «Drive Belt Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) .
  12. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  13. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  1. J 37872 Compressor Clutch Holding Tool. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  2. J 6083 Snap Ring Pliers. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  3. J 39400-A Halogen Leak Detector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  1. Remove the accessory drive belt from the A/C compressor. Refer to «Drive Belt Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) for the 3.8L engine or «Drive Belt Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) for the 3.6L (LY7) engine.
  2. Remove the lower air deflector. Refer to «Radiator Air Baffle and Deflector Replacement - Lower»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) .
  3. Remove and discard the compressor clutch plate bolt. Use the J 37872 to hold the compressor clutch plate from turning. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  4. Remove the compressor clutch plate from the compressor.
  5. Remove the compressor pulley snap ring using the J 6083 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  6. Remove the compressor pulley from the compressor.
  7. Remove the compressor clutch coil snap ring using the J 6083 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  8. Remove the compressor clutch coil from the compressor.
  1. Carefully clean the clutch plate bolt threads with a M6x1.0 tap. Carefully blow out debris with compressed air.
  2. Install the compressor clutch coil to the compressor.
  3. Install the compressor clutch coil snap ring using the J 6083 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  4. Install the compressor pulley to the compressor.
  5. Install the compressor pulley snap ring using the J 6083 . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  6. Place a small amount of oil on the 0.4 mm (0.016 in) air gap shim and place inside the clutch drive plate.
  7. Install the compressor clutch plate to the compressor.
  8. Measure the air gap between the pulley and the drive plate. Adjust the shims to achieve a 0.3-0.6 mm (0.012-0.024 in) air gap.
  9. Install the clutch drive plate bolt.
  10. Tighten the compressor clutch drive plate bolt. Use the J 37872 to hold the compressor clutch plate from turning. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) . Tighten: Tighten the bolt to 12 N.m (106 lb in).
  11. Install the lower air deflector. Refer to «Radiator Air Baffle and Deflector Replacement - Lower»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) .
  12. Install the accessory drive belt to the A/C compressor. Refer to «Drive Belt Replacement (L26)»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) for the 3.8L engine or «Drive Belt Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-36l-ly7-repair-instructions-1-of-5) for the 3.6L (LY7) engine.
  13. Leak test the fittings using the J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Raise and support the vehicle. Refer to «Lifting and Jacking the Vehicle»(/buick/lacrosse/i-2004-2009/remont/hoistjack/#general-information__lifting-and-jacking-the-vehicle) in General Information.
  3. Remove the high pressure relief valve.
  4. Cap or tape the A/C compressor.
  1. Remove the cap or tape from the A/C compressor.
  2. Lubricate the O-ring on the high pressure relief valve. Refer to «O-Ring Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  3. Install the high pressure relief valve. Tighten: Tighten the valve to 8 N.m (70 lb in).
  4. Lower the vehicle.
  5. Evacuate and recharge the refrigerant system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  6. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  1. Remove the seal washer from the A/C refrigerant component.
  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.
  4. Discard the sealing washer.
  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.
  5. Assemble the remaining A/C refrigerant components. Refer to the appropriate repair procedure.
  1. Disassemble the A/C refrigerant components. Refer to the appropriate repair procedure.
  2. Remove the O-ring seals from the A/C refrigerant component.
  3. Inspect the O-ring seals for signs of damage.
  4. Inspect the A/C refrigerant components for damage or burrs. Repair if necessary.
  5. Cap or tape the A/C refrigerant components.
  6. Discard the O-ring seals.
  1. Inspect the new O-ring seals 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.
  4. Lightly coat the new O-ring seals with mineral base 525 viscosity refrigerant oil.
  5. Carefully slide the new O-ring seals onto the A/C refrigerant component.
  6. The O-ring seals must be fully seated.
  7. Assemble the A/C components. Refer to the appropriate repair procedure.

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant from the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Locate the A/C coupling assembly's locking tab access slots.
  3. Carefully insert a small flat bladed screwdriver into the first locking tab access slot and gently lift the locking tab to release the lock.
  4. Carefully insert a small flat bladed screwdriver into the second locking tab access slot and gently lift the locking tab to release the lock.
  5. Open and remove the A/C coupling assembly from the A/C refrigerant component.
  1. Install the A/C coupling assembly to the A/C refrigerant component.
  2. Close the A/C coupling assembly.
  3. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  4. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine.
  3. Remove the A/C compressor hose nut from the condenser.
  4. Disconnect the A/C compressor hose from the condenser.
  5. Remove the A/C compressor hose nut from the evaporator tube.
  6. Remove the A/C compressor hose from the evaporator tube.
  7. Remove the A/C compressor hose nut from the A/C compressor.
  8. Remove the A/C compressor hose from the A/C compressor.
  9. Remove and discard all sealing washers.
  1. Install new sealing washers onto the A/C compressor hose assembly. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Install the A/C compressor hose to the A/C compressor.
  3. Install the A/C compressor hose nut to the A/C compressor. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  4. Install new seals washers to the A/C compressor hose assembly and evaporator tube. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  5. Install the A/C compressor hose to the evaporator tube.
  6. Install the A/C compressor hose to evaporator tube nut. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  7. Install the A/C compressor hose to the condenser.
  8. Install the A/C compressor hose nut to the condenser. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  9. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine.
  10. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  11. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  3. Remove the A/C compressor hose nut from the condenser.
  4. Disconnect the A/C compressor hose from the condenser.
  5. Remove the A/C compressor hose nut from the evaporator tube.
  6. Remove the A/C compressor hose from the evaporator tube.
  7. Remove the A/C compressor hose nut from the A/C compressor.
  8. Remove the A/C compressor hose from the A/C compressor.
  9. Remove and discard all sealing washers.
  1. Install new sealing washers onto the A/C compressor hose assembly. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Install the A/C compressor hose to the A/C compressor.
  3. Install the A/C compressor hose nut to the A/C compressor. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  4. Install new seals washers to the A/C compressor hose assembly and evaporator tube. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  5. Install the A/C compressor hose to the evaporator tube.
  6. Install the A/C compressor hose to evaporator tube nut. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  7. Install the A/C compressor hose to the condenser.
  8. Install the A/C compressor hose nut to the condenser. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  9. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  10. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  11. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Scheme 15

Scheme 15: Air Conditioning Evaporator Thermal Expansion Valve Tube Replacement
Scheme 15: Air Conditioning Evaporator Thermal Expansion Valve Tube Replacement
CalloutComponent Name
NOTE: Refer to Fastener Notice . Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedure Recover the refrigerant. Refer to Refrigerant Recovery and Recharging . Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement for the 3.8L engine or Air Cleaner Assembly Replacement for the 3.6L (LY7) engine. Remove the brake pressure modulator valve bracket. Refer to Brake Pressure Modulator Valve (BPMV) Bracket Replacement .
1Nut, A/C Evaporator TXV Tube Tighten: 17 N.m (12.5 lb ft)
2Washer, Sealing Tip: Remove and discard the sealing washers. Refer to Sealing Washer Replacement .
3Connector, A/C Condenser Tube Tip: Remove the connector tube. Refer to A/C Line/Tube Connector Removal/Replacement .
4O-ring, Seal Tip: Remove and discard O-ring. Refer to O-Ring Replacement .
5Nut, A/C Compressor and Evaporator Tube Tighten: 17 N.m (12.5 lb ft)
6Washer, Sealing Tip: Remove and discard the sealing washers. Refer to Sealing Washer Replacement .
7Bolt, A/C Condenser and A/C Evaporator Tube Clamp Tighten: 10 N.m (89 lb in)
8Tube Assembly, A/C Evaporator TXV
NOTE
Refer to Fastener Notice .

Air Conditioning Evaporator Thermal Expansion Valve Tube Replacement

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine or «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  3. Remove the A/C line coupling from the evaporator tube to condenser tube. Refer to «A/C Line/Tube Connector Removal/Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  4. Disconnect the evaporator tube from the condenser.
  5. Remove and discard the O-ring seals. Refer to «O-Ring Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  6. Remove the refrigerant filter from the evaporator tube.
  1. Replace the O-ring seals on the evaporator tube. Refer to «O-Ring Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Install a new refrigerant filter to the evaporator tube.
  3. Connect the evaporator tube to the condenser.
  4. Install the A/C line coupling to the evaporator tube and condenser tube. Refer to «A/C Line/Tube Connector Removal/Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  5. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine or «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  6. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  7. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

Remove the A/C compressor control relay from the electrical center. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.

Install the A/C compressor control relay into the electrical center. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.

J 39037 Charge Valve Octagon Socket. See Special Tools .

  1. Remove the service port cap.
  2. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  3. Use the J 39037 to remove the service port. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  1. Replace the O-ring. Refer to «O-Ring Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Install the service port valve. Tighten: Tighten the valve to 11 N.m (98 lb in).
  3. Evacuate and charge the system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  4. Leak test the A/C service port. Refer to «Leak Testing»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  5. Install the service port cap.

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant from the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the evaporator tube to thermostatic expansion valve (TXV) nut (1).
  3. Disconnect the evaporator outlet and inlet tube from the TXV.
  4. Remove and discard the sealing washers.
  5. Cap off the evaporator inlet and outlet tube.
  6. Remove the TXV to evaporator bolts.
  7. Remove the TXV from the evaporator core.
  8. Remove and discard the sealing washers.
  1. Install the new sealing washers onto the evaporator core. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Install the TXV to the evaporator core.
  3. Install the TXV to evaporator bolts. Tighten: Tighten the bolts to 7 N.m (62 lb in).
  4. Remove the cap or tape from the evaporator inlet and outlet tubes.
  5. Install the new sealing washers onto the evaporator inlet and outlet tubes. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  6. Install the evaporator outlet and inlet tube to the TXV.
  7. Install the evaporator tube nut (1). Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  8. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  9. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine or «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  2. Disconnect the electrical connector from the A/C refrigerant pressure sensor.
  3. Remove the refrigerant pressure sensor from the liquid line.
  1. Install the new O-ring seal. Refer to «O-Ring Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Install the refrigerant pressure sensor to the liquid line. Tighten: Tighten the sensor to 4.7 N.m (41 lb in).
  3. Connect the electrical connector to the A/C refrigerant pressure sensor.
  4. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine or «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  5. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .

J 39400-A Halogen Leak Detector. See Special Tools .

  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the radiator. Refer to «Radiator Replacement»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) .
  3. Remove the A/C line coupling from the condenser tube to evaporator tube. Refer to «A/C Line/Tube Connector Removal/Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  4. Remove the A/C compressor line nut from the condenser and position the A/C compressor line aside.
  5. Remove the condenser from the vehicle.
  6. Remove and discard the O-ring seals and seal washer.
  1. If replacing the condenser, add refrigerant oil to the condenser. Refer to «Refrigerant System Capacities»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__refrigerant-system-capacities) for system capacity information.
  2. Install the condenser to the vehicle.
  3. Install a new seal washer onto the A/C compressor hose. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  4. Install new O-ring seals onto the evaporator tube. Refer to «O-Ring Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  5. Install the evaporator tube to the condenser tube.
  6. Install the A/C line coupling to the evaporator tube and the condenser tube. Refer to «A/C Line/Tube Connector Removal/Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  7. Install the A/C compressor hose to the condenser.
  8. Install the A/C compressor hose block fitting nut to the condenser. Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  9. Install the radiator. Refer to «Radiator Replacement»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) .
  10. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  11. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  1. Remove the right side instrument panel (I/P) insulator. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  2. Disconnect the electrical connector from the blower control module.
  3. Remove the 2 heat stakes from the blower control module using a small chisel.
  4. Remove the blower control module.
  1. Install the blower control module.
  2. Install the 2 new screws in the pre-drilled holes to the side of the heat stakes in the blower control module and the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  3. Connect the electrical connector to the blower control module.
  4. Install the right side I/P insulator. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  1. J 39400-A Halogen Leak Detector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  2. J 38185 Hose Clamp Pliers
  1. Recover the refrigerant. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Disconnect the battery negative cable. Refer to «Battery Negative Cable Disconnect/Connect Procedure (L26)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) .
  3. Remove the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine or «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  4. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) for the 3.8L engine.
  5. Drain the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) .
  6. Remove the instrument panel (I/P) trim pad. Refer to «Trim Pad Replacement - Instrument Panel (I/P)»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) .
  7. Remove the bolt from the accessory wiring junction block.
  8. Disengage the junction block tabs from the passenger knee bolster. Remove the junction block from the knee bolster.
  9. Remove the brake pedal nut and bolt.
  10. Remove the brake pedal brace bolts from the I/P carrier cross car beam.
  11. Disconnect any ground wires, as necessary.
  12. Reposition the I/P wiring harness out of the way.
  13. Remove the bracket bolt from the HVAC module assembly right support (2).
  14. Remove the bracket bolts from the HVAC module assembly lower support (1).
  15. Remove the bracket bolts from the HVAC module assembly upper support.
  16. Remove the right and the left I/P carrier bolts.
  17. Remove the I/P carrier.
  18. Remove the nut (1) that secures the evaporator tube to the thermostatic expansion valve (TXV).
  19. Disconnect the evaporator tube from the TXV.
  20. Remove the seal washers and discard.
  21. Use J 38185 in order to position aside the inlet heater hose clamp at the heater core.
  22. Use J 38185 in order to position aside the outlet heater hose clamp at the heater core.
  23. Disconnect the inlet heater hose from the heater core.
  24. Disconnect the outlet heater hose from the heater core.
  25. Disconnect the electrical connectors from the HVAC module assembly.
  26. Remove the evaporator drain elbow.
  27. Remove the nuts which secure the HVAC module assembly to the dash.
  28. Remove the HVAC module assembly.
  29. Remove all of the seals (1, 2, 3) from the outer HVAC module assembly.
  1. Install new seals (1, 2, 3) to the outer HVAC module assembly.
  2. Install the HVAC module assembly to the vehicle.
  3. Install the nuts which secure the HVAC module assembly to the dash. Tighten: Tighten the nuts to 10 N.m (89 lb in).
  4. Install the evaporator drain elbow.
  5. Connect the electrical connectors to the HVAC module assembly.
  6. Install the I/P carrier to the vehicle. Align the I/P carrier to the HVAC module assembly and the hinge pillars.
  7. Install the bolts to the right and the left I/P carrier. Tighten: Tighten the bolts to 25 N.m (18 lb ft).
  8. Install the bolts to the HVAC module assembly upper support bracket. Tighten: Tighten the bolts to 4 N.m (36 lb in).
  9. Install the bolts to the HVAC module assembly lower support bracket (1). Tighten: Tighten the bolts to 4 N.m (36 lb in).
  10. Install the bolt to the HVAC module assembly right support bracket (2). Tighten: Tighten the bolt to 4 N.m (36 lb in).
  11. Position the I/P wiring harness to the original position.
  12. Connect any disconnected ground wires.
  13. Install the brake pedal brace bolts to the I/P carrier.
  14. Position the brake pedal to the brake pedal brace.
  15. Install the brake pedal bolt and nut. Refer to «Brake Pedal Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical-hydraulic/#hydraulic-brake-system) .
  16. Seat the bottom junction block tabs and snap the top of the junction block to the passenger knee bolster.
  17. Install the junction block bolt. Tighten: Tighten the bolts to 10 N.m (89 lb in).
  18. Install the I/P trim pad. Refer to «Trim Pad Replacement - Instrument Panel (I/P)»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) .
  19. Connect the inlet heater hose to the heater core.
  20. Connect the outlet heater hose to the heater core.
  21. Use J 38185 in order to reposition the inlet heater hose clamp to the heater core.
  22. Use J 38185 in order to reposition the outlet heater hose clamp to the heater core.
  23. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) for the 3.8L engine.
  24. Fill the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) .
  25. Install new sealing washers on the evaporator tube. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  26. Connect the evaporator tube to the TXV.
  27. Install the evaporator tube to the TXV block fitting nut (1). Tighten: Tighten the nut to 17 N.m (12.5 lb ft).
  28. Install the air cleaner assembly. Refer to «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-38l-introduction-2-of-2) for the 3.8L engine or «Air Cleaner Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/testing-diagnostics/#engine-control-system-36l-ly7-introduction-2-of-2) for the 3.6L (LY7) engine.
  29. Connect the battery negative cable. Refer to «Battery Negative Cable Disconnect/Connect Procedure (L26)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) .
  30. Evacuate and recharge the A/C system. Refer to «Refrigerant Recovery and Recharging»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  31. Leak test the fittings of the component using J 39400-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__special-tools) .
  1. Remove the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the screws that secure the recirculation housing to the HVAC module assembly.
  3. Remove the recirculation housing from the HVAC module assembly.
  4. Remove the screws that secure the mode actuator to the HVAC module assembly.
  5. Remove the mode actuator from the HVAC module assembly.
  6. Remove the bolts that secure the TXV to the evaporator core.
  7. Remove the TXV from the evaporator core.
  8. Discard the old seal rings from the evaporator core.
  9. Remove the screws that secure HVAC module assembly upper case to the HVAC module assembly lower case.
  10. Remove the heat stakes that secure the HVAC module assembly upper case to the HVAC module lower case using a small chisel.
  11. Separate the HVAC module assembly case (1).
  12. Remove the evaporator core.
  1. If replacing the evaporator, add refrigerant oil to the evaporator. Refer to «Refrigerant System Capacities»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning__refrigerant-system-capacities) for system capacity information.
  2. Install a new side seal to the evaporator core.
  3. Install a new upper seal to the evaporator core.
  4. Install 2 new lower seals to the evaporator core.
  5. Install the evaporator core into the HVAC module assembly lower case.
  6. From the inside of the upper case, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  7. Align and attach the upper and lower HVAC module assembly case.
  8. Install the removed screws that secure the HVAC module assembly upper case to the HVAC module assembly lower case to their original position. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  9. Install new screws that will secure the HVAC module assembly upper case to the HVAC module assembly lower case in the predrilled holes adjacent to the heat stakes. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  10. Install the mode actuator.
  11. Install the screws that secure the mode actuator to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  12. Install the recirculation housing to the HVAC module assembly.
  13. Install the screws that secure the recirculation housing to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  14. Install new sealing washers on the evaporator core. Refer to «Sealing Washer Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  15. Install the TXV to the evaporator core.
  16. Install the bolts that secure the TXV to evaporator core. Tighten: Tighten the bolts to 7 N.m (62 lb in).
  17. Install the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .

Scheme 16

Scheme 16: Heater Hoses Replacement (LY7)
Scheme 16: Heater Hoses Replacement (LY7)
CalloutComponent Name
NOTE: Refer to Fastener Notice . Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedure: Drain the cooling system. Refer to Draining and Filling Cooling System (L26 Static Fill) or Draining and Filling Cooling System (LY7 Static Fill) or Draining and Filling Cooling System (L26, LY7, GE 47716 Fill) .
1Hose, Heater Inlet Tip: Use J 38185 Hose Clamp Plier to release the clamp on the heater hose.
2Hose, Heater Outlet Tip: Use J 38185 Hose Clamp Plier to release the clamp on the heater hose.
NOTE
Refer to Fastener Notice .

Heater Hoses Replacement (LY7)

Heater Hose Replacement - Inlet (LY7)

CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedure: Drain the cooling system. Refer to Draining and Filling Cooling System (L26 Static Fill) or Draining and Filling Cooling System (LY7 Static Fill) or Draining and Filling Cooling System (L26, LY7, GE 47716 Fill) in Engine Cooling.
1Hose, Radiator Inlet Tip: Use J 38185 hose clamp plier to release the clamp on the radiator inlet hose.
NOTE
Refer to Fastener Notice in Cautions and Notices.

Heater Hose Replacement - Inlet (LY7)

J 38185 Hose Clamp Pliers

  1. Drain the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.
  2. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  3. Use J 38185 in order to position aside the heater hose inlet clamp at the pipe adapter.
  4. Disconnect the heater inlet hose from the pipe adapter.
  5. Remove the heater hose from the support bracket.
  6. Use J 38185 in order to position aside the heater core inlet hose clamp.
  7. Disconnect the heater inlet hose from the heater core.
  1. Connect the heater inlet hose to the heater core.
  2. Use J 38185 in order to secure the heater core hose inlet clamp.
  3. Install the heater hose to the support bracket.
  4. Connect the heater inlet hose to the pipe adapter.
  5. Use J 38185 in order to secure the heater hose inlet clamp.
  6. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  7. Fill the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.

Heater Hose Replacement - Outlet (LY7)

CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedure: Drain the cooling system. Refer to Draining and Filling Cooling System (L26 Static Fill) or Draining and Filling Cooling System (LY7 Static Fill) or Draining and Filling Cooling System (L26, LY7, GE 47716 Fill) in Engine Cooling.
1Hose, Heater Inlet
2Hose, Heater Outlet Tip: Use J 38185 hose clamp plier to release the clamp on the heater hose.
NOTE
Refer to Fastener Notice in Cautions and Notices.

Heater Hose Replacement - Outlet (LY7)

J 38185 Hose Clamp Pliers

  1. Drain the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.
  2. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  3. Use J 38185 in order to position aside the heater hose outlet clamp at the pipe adapter.
  4. Disconnect the heater outlet hose from the pipe adapter.
  5. Remove the heater hose from the support bracket.
  6. Use J 38185 in order to position aside the heater core outlet hose clamp.
  7. Disconnect the heater outlet hose from the heater core.
  1. Connect the heater outlet hose to the heater core.
  2. Use J 38185 in order to secure the heater core hose outlet clamp.
  3. Install the heater hose to the support bracket.
  4. Connect the heater outlet hose to the pipe adapter.
  5. Use J 38185 in order to secure the heater hose outlet clamp.
  6. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  7. Fill the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.

Scheme 17

Scheme 17: Heater Pipe Replacement
Scheme 17: Heater Pipe Replacement
CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedure Drain the cooling system. Refer to Draining and Filling Cooling System (L26 Static Fill) , Draining and Filling Cooling System (LY7 Static Fill) or Draining and Filling Cooling System (L26, LY7, GE 47716 Fill) in Engine Cooling. Remove heater hoses from heater pipe assembly. Refer to Heater Hose Replacement - Inlet (LY7) , Heater Hose Replacement - Inlet (L26) , Heater Hose Replacement - Outlet (LY7) or Heater Hose Replacement - Outlet (L26) . Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 3.6L (LY7).
1Hose, Heater Inlet Tip: Use J 38185 Hose Clamp Pliers to release the clamp on the heater hose. Only remove hose from heater pipe.
2Hose, Heater Outlet Tip: Use J 38185 Hose Clamp Pliers to release the clamp on the heater hose. Only remove hose from heater pipe.
3Bolt, Heater Pipe Assembly (Qty: 2) Tighten: 16 N.m (12 lb ft)
4Pipe, Heater Assembly
5Gasket, Heater Pipe Assembly
6O-Ring, Heater Pipe Assembly
NOTE
Refer to Fastener Notice in Cautions and Notices.

Heater Pipe Replacement

J 38185 Hose Clamp Pliers

  1. Drain the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.
  2. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  3. Disconnect the heater inlet hose from the pipe adapter.
  4. Use J 38185 in order to position aside the heater hose clamp.
  5. Remove the heater pipe adapter mounting bolt.
  6. Remove the heater pipe adapter.
  1. Lubricate the O-ring with coolant.
  2. Install the heater pipe adapter
  3. Install the heater pipe adapter mounting bolt. Tighten: Tighten the bolt to 6 N.m (53 lb in).
  4. Connect the heater inlet hose to the pipe adapter.
  5. Use J 38185 in order to secure the heater core hose clamp.
  6. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  7. Fill the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.

J 38185 Hose Clamp Pliers

  1. Drain the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.
  2. Remove the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  3. Remove the heater outlet hose from the pipe adapter.
  4. Use J 38185 in order to position aside the heater hose clamp.
  5. Remove the heater outlet adapter pipe mounting bolt.
  6. Remove the heater outlet adapter pipe.
  1. Lubricate the O-ring with coolant.
  2. Install the heater outlet adapter pipe.
  3. Install the heater outlet adapter pipe mounting bolt. Tighten: Tighten the bolt to 6 N.m (53 lb in).
  4. Install the heater outlet hose to the pipe adapter.
  5. Use J 38185 in order to secure the heater core hose clamp.
  6. Install the fuel injector sight shield. Refer to «Fuel Injector Sight Shield Replacement»(/buick/lacrosse/i-2004-2009/remont/mechanical/#engine-mechanical-38l) in Engine Mechanical - 3.8L.
  7. Fill the cooling system. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.
  1. Position the windshield wipers in the UP position, by keying the ignition OFF when the wiper reach the desired position.
  2. Open the hood.
  3. Position aside the rear hood seal halfway to the center. Refer to «Seal Replacement - Hood Rear»(/buick/lacrosse/i-2004-2009/remont/exterior-body-panels/#body-front-end) in Body Front End.
  4. Remove the washer hose from the right air inlet grill panel and position aside.
  5. Remove the two push pin retainers from the right air inlet grill panel.
  6. Position the left side of the right air inlet grill panel on to the windshield.
  7. Remove the passenger compartment air filter.
  1. Install the passenger compartment air filter.
  2. Install the air inlet grill panel into position.
  3. Install the push pin retainers to the air inlet grill panel.
  4. Position the washer hose in to the right air inlet grill panel clips.
  5. Install the rear hood seal. Refer to «Seal Replacement - Hood Rear»(/buick/lacrosse/i-2004-2009/remont/exterior-body-panels/#body-front-end) in Body Front End.
  6. Close the hood.
  7. Return the windshield wipers to the PARK position.
  1. Remove the right side instrument panel insulator. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
  2. Disconnect the blower motor electrical connector.
  3. Remove the blower motor mounting screws.
  4. Remove the blower motor.
  1. Install the blower motor.
  2. Install the blower motor screws. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  3. Connect the blower motor electrical connector.
  4. Install the right side instrument panel insulator. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.

Scheme 18

Scheme 18: Air Distributor Duct Replacement
Scheme 18: Air Distributor Duct Replacement
CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedures Remove the instrument panel carrier. Refer to Instrument Panel (I/P) Carrier Replacement in Instrument Panel, Gages, and Console. Remove the temperature sensor upper right. Refer to Air Temperature Sensor Replacement - Upper Right . Remove the temperature sensor upper left. Refer to Air Temperature Sensor Replacement - Upper Left .
1Bolt, Duct Assembly - Air Distribution Tighten: 8 N.m (71 lb in)
2Screw, Duct Assembly - Air Distribution Tighten: 1.5 N.m (71 lb in)
3Duct Assembly - Air Distribution
4Nut Speed, Distributor Assembly Air Right Hand Tighten: 1.5 N.m (71 lb in)
5Screw, Distributor Assembly Air Right Hand Tighten: 8 N.m (71 lb in)
6Distributor Assembly Air Right Hand
7Screw, Distributor Assembly Air Left Hand Tighten: 8 N.m (71 lb in)
8Distributor Assembly Air Left Hand
9Screw, Distributor Assembly Air Tighten: 8 N.m (71 lb in)
10Distributor Assembly Air
11Screw, Duct Assembly Air Distributor Duct Right Hand Tighten: 8 N.m (71 lb in)
12Duct Assembly Air Distributor Duct Right Hand
13Screw, Duct Assembly Air Distributor Duct Left Hand Tighten: 8 N.m (71 lb in)
14Duct Assembly Air Distributor Duct Left Hand
NOTE
Refer to Fastener Notice in Cautions and Notices.

Air Distributor Duct Replacement

Scheme 19

Scheme 19: Air Outlet Replacement - Side Window (Right)
Scheme 19: Air Outlet Replacement - Side Window (Right)
CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications .
1Outlet, Air Instrument Panel - Right
2Panel, Fuse Block Access
3Screw, Air Outlet Side Window Tip: Use a flexible driver with a Phillips bit to remove the side window defog outlet grille screw. Tighten: 2 N.m (18 lb in)
4Outlet, Air Side Window - Right
NOTE
Refer to Fastener Notice in Cautions and Notices.

Air Outlet Replacement - Side Window (Right)

Scheme 20

Scheme 20: Air Outlet Replacement - Side Window (Left)
Scheme 20: Air Outlet Replacement - Side Window (Left)
CalloutComponent Name
Fastener Tightening Specifications: Refer to Fastener Tightening Specifications .
1Outlet, Air Side Window - Left
2Outlet, Air Instrument Panel - Left

Air Outlet Replacement - Side Window (Left)

Air Outlet Replacement - Instrument Panel - Left

CalloutComponent Name
Fastener Tightening Specifications: Refer to Fastener Tightening Specifications .
1Air Instrument Panel Outlet - Left

Air Outlet Replacement - Instrument Panel - Left

Scheme 21

Scheme 21: Air Outlet Replacement - Instrument Panel - Center
Scheme 21: Air Outlet Replacement - Instrument Panel - Center
CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications .
1Screw, Instrument Panel Cluster Bezel Tip: The screw can be accessed by opening the instrument panel compartment. Tighten: 2 N.m (18 lb in)
2Trim Plate, Instrument Panel Cluster Tip: Pull the trim plate away from the instrument panel far enough to disconnect the headlamp switch electrical connector, then remove from the vehicle.
3Outlet Assembly, Instrument Panel Center Air
NOTE
Refer to Fastener Notice in Cautions and Notices.

Air Outlet Replacement - Instrument Panel - Center

Scheme 22

Scheme 22: Air Outlet Replacement - Instrument Panel - Right
Scheme 22: Air Outlet Replacement - Instrument Panel - Right
CalloutComponent Name
Fastener Tightening Specifications: Refer to Fastener Tightening Specifications .
1Outlet, Air Instrument Panel - Right

Air Outlet Replacement - Instrument Panel - Right

Scheme 23

Scheme 23: Air Outlet Replacement - Defroster
Scheme 23: Air Outlet Replacement - Defroster
CalloutComponent Name
Fastener Tightening Specifications: Refer to Fastener Tightening Specifications .
1Outlet, Air Defroster Tip: Held in with clips (Qty: 4).
2Sensor, Daytime Running Lamps Tip: Remove the daytime running lamps sensor from the air outlet defroster.
3Clip, Air Outlet Defroster (Qty: 4)

Air Outlet Replacement - Defroster

  1. Remove the floor carpet. Refer to «Carpet Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
  2. Remove the rear floor air outlet duct (1) from the holes in the floor reinforcement.
  3. Disconnect the rear floor air outlet duct from the heater core outlet cover.
  4. Remove the rear floor air outlet duct.
  1. Install the rear floor air outlet duct.
  2. Connect the rear floor air outlet duct to the heater core outlet cover.
  3. Position the rear floor air outlet duct (1) to the holes in the floor reinforcement and press into place.
  4. Install the floor carpet. Refer to «Carpet Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
  1. Remove the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the screws that secure the recirculation housing to the HVAC module assembly.
  3. Remove the recirculation housing from the HVAC module assembly.
  4. Remove the screws that secure the mode actuator to the HVAC module assembly.
  5. Remove the mode actuator from the HVAC module assembly.
  6. Remove the screws that secure HVAC module assembly upper case to the HVAC module assembly lower case.
  7. Remove the heat stakes that secure the HVAC module assembly upper case to the HVAC module lower case using a small chisel.
  8. Separate the HVAC module assembly case (1).
  9. Remove the screws that secure the air temperature actuator to the HVAC module assembly upper case.
  10. Remove the air temperature actuator from the HVAC module assembly upper case.
  11. Remove the air temperature door from the HVAC module assembly upper case.
  1. Install the air temperature door to the HVAC module assembly upper case.
  2. Install the air temperature actuator to the HVAC module assembly upper case.
  3. Install the screws that secure the air temperature actuator to the HVAC module assembly upper case. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  4. From the inside of the upper case, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  5. Align and attach the upper and lower HVAC module assembly case.
  6. Install the removed screws that secure the HVAC module assembly upper case to the HVAC module assembly lower case to their original position. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  7. Install new screws that will secure the HVAC module assembly upper case to the HVAC module assembly lower case in the locations adjacent to the heat stakes. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  8. Install the mode actuator.
  9. Install the screws that secure the mode actuator to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  10. Install the recirculation housing to the HVAC module assembly.
  11. Install the screws that secure the recirculation housing to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  12. Install the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  1. Remove the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the screws that secure the recirculation housing to the HVAC module assembly.
  3. Remove the recirculation housing from the HVAC module assembly.
  4. Remove the screws that secure the mode actuator to the HVAC module assembly.
  5. Remove the mode actuator from the HVAC module assembly.
  6. Remove the screws that secure HVAC module assembly upper case to the HVAC module assembly lower case.
  7. Remove the heat stakes that secure the HVAC module assembly upper case to the HVAC module lower case using a small chisel.
  8. Separate the HVAC module assembly case (1).
  9. Remove the screws that secure the air temperature actuator to the HVAC module assembly upper case.
  10. Remove the air temperature actuator from the HVAC module assembly upper case.
  11. Remove the air temperature door from the HVAC module assembly upper case.
  12. Remove the right air temperature door from the air temperature door assembly.
  1. Install the right air temperature door to the air temperature door assembly.
  2. Install the air temperature door to the HVAC module assembly upper case.
  3. Install the air temperature actuator to the HVAC module assembly upper case.
  4. Install the screws that secure the air temperature actuator to the HVAC module assembly upper case. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  5. From the inside of the upper case, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  6. Align and attach the upper and lower HVAC module assembly case.
  7. Install the removed screws that secure the HVAC module assembly upper case to the HVAC module assembly lower case to their original position. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  8. Install new screws that will secure the HVAC module assembly upper case to the HVAC module assembly lower case in the locations adjacent to the heat stakes. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  9. Install the mode actuator.
  10. Install the screws that secure the mode actuator to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  11. Install the recirculation housing to the HVAC module assembly.
  12. Install the screws that secure the recirculation housing to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  13. Install the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  1. Remove the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  2. Remove the screws that secure the recirculation housing to the HVAC module assembly.
  3. Remove the recirculation housing from the HVAC module assembly.
  4. Remove the screws that secure the mode actuator to the HVAC module assembly.
  5. Remove the mode actuator from the HVAC module assembly.
  6. Remove the screws that secure HVAC module assembly upper case to the HVAC module assembly lower case.
  7. Remove the heat stakes that secure the HVAC module assembly upper case to the HVAC module lower case using a small chisel.
  8. Separate the HVAC module assembly case (1).
  9. Remove the screws that secure the air temperature actuator to the HVAC module assembly upper case.
  10. Remove the air temperature actuator from the HVAC module assembly upper case.
  11. Remove the air temperature door from the HVAC module assembly upper case.
  12. Remove the left air temperature door from the air temperature door assembly.
  1. Install the left air temperature door to the air temperature door assembly.
  2. Install the air temperature door to the HVAC module assembly upper case.
  3. Install the air temperature actuator to the HVAC module assembly upper case.
  4. Install the screws that secure the air temperature actuator to the HVAC module assembly upper case. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  5. From the inside of the upper case, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  6. Align and attach the upper and lower HVAC module assembly case.
  7. Install the removed screws that secure the HVAC module assembly upper case to the HVAC module assembly lower case to their original position. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  8. Install new screws that will secure the HVAC module assembly upper case to the HVAC module assembly lower case in the locations adjacent to the heat stakes. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  9. Install the mode actuator.
  10. Install the screws that secure the mode actuator to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  11. Install the recirculation housing to the HVAC module assembly.
  12. Install the screws that secure the recirculation housing to the HVAC module assembly. Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  13. Install the HVAC module assembly. Refer to «HVAC Module Assembly Replacement»(/buick/lacrosse/i-2004-2009/remont/automatic-hvac-system/#heating-ventilation-and-air-conditioning) .
  1. Disconnect the battery negative cable. Refer to «Battery Negative Cable Disconnect/Connect Procedure (L26)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) in Engine Electrical.
  2. Remove the instrument panel (I/P) trim pad. Refer to «Trim Pad Replacement - Instrument Panel (I/P)»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  3. Remove the bolt from the accessory wiring junction block.
  4. Disengage the junction block tabs from the passenger knee bolster. Remove the junction block from the knee bolster.
  5. Remove the booster push rod from the brake pedal.
  6. Remove the brake pedal bolt. Remove the brake pedal.
  7. Remove the brake pedal brace bolts from the I/P carrier cross car beam.
  8. Lower the body control module (BCM) away from the I/P carrier.
  9. Disconnect any ground wires, as necessary.
  10. Reposition the I/P wiring harness out of the way.
  11. Remove the bracket bolts from the HVAC module assembly lower support (1).
  12. Remove the bracket bolts from the HVAC module assembly RH support (2).
  13. Remove the bracket bolts from the HVAC module upper support
  14. Remove the right and the left I/P carrier bolts.
  15. Remove the I/P carrier.
  16. Remove the two rearward retaining screws from the recirculation housing.
  17. Remove the retaining screws from the mode valve assembly.
  18. Remove the three heat stakes from the mode valve assembly using a small chisel.
  19. Remove the screws from the mode valve actuator.
  20. Remove the mode valve actuator from the HVAC module assembly.
  21. Slowly lift the rearward side of the mode valve assembly up and to the left to remove the mode valve assembly.
  1. From the inside of the mode valve assembly, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  2. Install the right front edge of the mode valve assembly under the recirculation housing.
  3. Install the mode valve assembly to the HVAC module assembly.
  4. Install the two rearward retaining screws to the recirculation housing.
  5. Install three new screws in the locations adjacent to the removed heat stakes in the mode valve assembly.
  6. Install the screws that were removed from the mode valve assembly to there original position.
  7. Tighten the recirculation housing, mode valve assembly and heat stake replacement screws. Tighten: Tighten all the screws to 1.5 N.m (13 lb in).
  8. Position the mode actuator on to the HVAC module assembly.
  9. Install the mode valve actuator bolts. Tighten: Tighten the bolts to 1.5 N.m (13 lb in).
  10. Install the I/P carrier to the vehicle. Align the I/P carrier to the HVAC module and the hinge pillars.
  11. Install the bolts to the right and the left I/P carrier. Tighten: Tighten the bolts to 25 N.m (18 lb ft).
  12. Install the bolts to the HVAC module assembly upper support bracket. Tighten: Tighten the bolts to 4 N.m (36 lb in).
  13. Install the bolts to the HVAC module assembly lower support bracket (1). Tighten: Tighten the bolts to 4 N.m (36 lb in).
  14. Install the bolts to the HVAC module assembly RH support bracket (2). Tighten: Tighten the bolts to 4 N.m (36 lb in).
  15. Position the I/P wiring harness to the original position.
  16. Connect any disconnected ground wires.
  17. Install the BCM.
  18. Install the brake pedal brace bolts to the I/P carrier.
  19. Install the brake pedal and the brake pedal bolt.
  20. Install the booster push rod to the brake pedal.
  21. Seat the bottom junction block tabs and snap the top of the junction block to the passenger knee bolster.
  22. Install the junction block bolt. Tighten: Tighten the bolts to 10 N.m (89 lb in).
  23. Install the I/P trim pad. Refer to «Trim Pad Replacement - Instrument Panel (I/P)»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
  24. Connect the battery negative cable. Refer to «Battery Negative Cable Disconnect/Connect Procedure (L26)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) or «Battery Negative Cable Disconnect/Connect Procedure (LY7)»(/buick/lacrosse/i-2004-2009/remont/charging-system/#battery-charging-system-and-starting-system) in Engine Electrical.

Scheme 24

Scheme 24: Recirculation Door Replacement
Scheme 24: Recirculation Door Replacement
CalloutComponent Name
NOTE: Refer to Fastener Notice in Cautions and Notices. Fastener Tightening Specifications: Refer to Fastener Tightening Specifications . Preliminary Procedure: Remove the HVAC module assembly. Refer to HVAC Module Assembly Replacement .
1Screw, Actuator Recirculation (Qty: 2) Tip: Disconnect electrical connector. Tighten: 1.5 N.m (13 lb in)
2Actuator, Recirculation Door Tip: Tilt recirculation door assembly to insert tabs into the HVAC module assembly.
3Screw, Recirculation Door Assembly (Qty: 3) Tighten: 1.5 N.m (13 lb in)
4Door, Recirculation Assembly
NOTE
Refer to Fastener Notice in Cautions and Notices.

Recirculation Door Replacement

  1. Remove the right hand (RH) instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  2. Remove the left hand (LH) instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  3. Remove the floor carpet. Refer to «Carpet Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
  4. Remove the communication interface module. Refer to «Communication Interface Module Replacement»(/buick/lacrosse/i-2004-2009/remont/entertainment-systems/#cellular-communication-systems) in Cellular Communication.
  5. Remove the rear floor air outlet duct from the holes in the floor reinforcement.
  6. Disconnect the rear floor air outlet duct from the heater air outlet cover.
  7. Remove the rear floor air outlet duct.
  8. Remove the heater air outlet cover screws (2).
  9. Remove the heater air outlet cover heat stakes (1) with a small chisel.
  10. Remove the heater air outlet cover from the HVAC module assembly.
  11. Remove the heater core cover screws (2).
  12. Remove the heater core cover heat stakes (1) with a small chisel.
  13. Remove the heater core cover from the HVAC module assembly.
  1. From the inside of the heater core cover, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  2. Install the heater core cover to the HVAC module assembly.
  3. Install the heater core cover screws (2). Tighten: Tighten all screws to 1.5 N.m (13 lb in).
  4. From the inside of the heater air outlet cover, drill the dimples adjacent to the heat stakes using a 5.5 N.m (7/32 in) drill bit.
  5. Install the heater air outlet cover.
  6. Install the heater air outlet cover screws (2) Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  7. Connect the rear floor air outlet duct to the heater air outlet cover.
  8. Install the rear floor air outlet duct to the holes in the floor reinforcement.
  9. Install the communication interface module. Refer to «Communication Interface Module Replacement»(/buick/lacrosse/i-2004-2009/remont/entertainment-systems/#cellular-communication-systems) in Cellular Communication.
  10. Install the floor carpet. Refer to «Carpet Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
  11. Install the RH instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  12. Install the LH instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.

J 38185 Hose Clamp Pliers

  1. Drain the coolant. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.
  2. Use J 38185 in order to position aside the heater hose inlet and outlet clamps at the heater core.
  3. Disconnect the inlet and outlet heater hose from the heater core.
  4. Remove the RH instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  5. Remove the LH instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  6. Remove the floor carpet. Refer to «Carpet Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
  7. Remove the communication interface module. Refer to «Communication Interface Module Replacement»(/buick/lacrosse/i-2004-2009/remont/entertainment-systems/#cellular-communication-systems) in Cellular Communication.
  8. Remove the rear floor air outlet duct from the holes in the floor reinforcement.
  9. Disconnect the rear floor air outlet duct from the heater core outlet cover.
  10. Remove the rear floor air outlet duct.
  11. Remove the heater core outlet cover screws (2).
  12. Remove the heater core outlet cover heat stakes (1) with a small chisel.
  13. Remove the heater core outlet cover from the HVAC module assembly.
  14. Remove the heater core cover screws (2).
  15. Remove the heater core cover heat stakes (1) with a small chisel.
  16. Remove the heater core cover from the HVAC module assembly.
  17. Remove the heater core from the HVAC module assembly.
  18. Remove the heater core foam seal (1) from the HVAC module assembly.
  1. Install a new heater core foam seal (1) to the HVAC module assembly.
  2. Install the heater core to the HVAC module assembly.
  3. From the inside of the heater core cover, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  4. Install the heater core cover.
  5. Install the heater core cover screws to the heater core cover. Tighten: Tighten all the screws to 1.5 N.m (13 lb in).
  6. From the inside of the heater core outlet cover, drill the dimples adjacent to the heat stakes using a 5.5 mm (7/32 in) drill bit.
  7. Install the heater core outlet cover.
  8. Install the heater core outlet cover screws (2). Tighten: Tighten the screws to 1.5 N.m (13 lb in).
  9. Connect the rear floor air outlet duct to the heater core outlet cover.
  10. Install the rear floor air outlet duct to the holes in the floor reinforcement.
  11. Install the communication interface module. Refer to «Communication Interface Module Replacement»(/buick/lacrosse/i-2004-2009/remont/entertainment-systems/#cellular-communication-systems) in Cellular Communication.
  12. Install the floor carpet. Refer to «Carpet Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
  13. Install the RH instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  14. Install the RH instrument panel closeout/insulator panel. Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages, and Console.
  15. Connect the inlet and outlet heater hose to the heater core.
  16. Use J 38185 in order to reposition the heater hose inlet and outlet clamps to the heater core.
  17. Refill the coolant. Refer to «Draining and Filling Cooling System (L26 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) , «Draining and Filling Cooling System (LY7 Static Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) or «Draining and Filling Cooling System (L26, LY7, GE 47716 Fill)»(/buick/lacrosse/i-2004-2009/remont/cooling-system-mechanical/#engine-cooling-system) in Engine Cooling.

Special Tools

Special Tools Illustration Tool Number/Description J 6083 External Snap Ring Pliers J 37872 Universal Spanner Wrench J 38185 Hose Clamp Pliers J 39037 Charge Valve Octagon Socket J 39400-A Halogen Leak Detector J 41447 R-134A A/C Tracer Dye - Box of 24 J 42220 Universal 12V Leak Detection Lamp J 43600 ACR 2000 Air Conditioning Service Center J 43872 Fluorescent Dye Cleaner J 45037 A/C Oil Injector J 45268 A/C Flushing Adapter Kit J 46297 A/C Dye Injector Kit J 46297-12 Replacement Dye Cartridges

Scheme 25

Scheme 25: Special Tools
Scheme 25: Special Tools

Scheme 26

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Scheme 26

Scheme 27

Scheme 27
Scheme 27

Scheme 28

Scheme 28
Scheme 28

Scheme 29

Scheme 29
Scheme 29

Scheme 30

Scheme 30
Scheme 30

Scheme 31

Scheme 31
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Scheme 32

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Scheme 33
Scheme 33

See also:
• Diagnostic System Check - Vehicle
• Symptoms - HVAC Systems - Manual
• Symptoms - HVAC Systems - Automatic
• Moving Parts and Hot Surfaces Caution
• Too Hot in Vehicle
• Cooling System Description and Operation
• Cooling Fan Inoperative
• Engine Fails To Reach Normal Operating Temperature (LY7)
• Air Delivery Improper
• Drive Belt Excessive Wear Diagnosis
• Drive Belt Excessive Wear Diagnosis
• Drive Belt Tensioner Diagnosis
• Drive Belt Tensioner Diagnosis
• Drive Belt Replacement
• Vibration Analysis - Engine
• Trim Pad Replacement - Instrument Panel (I/P)
• Loss of Coolant
• Oil Leak Diagnosis
• Oil Leak Diagnosis
• Fluid Leak Diagnosis
• Power Steering Fluid Leaks
• Fastener Notice
• Splash Shield Replacement - Engine
• Lifting and Jacking the Vehicle
• Air Cleaner Assembly Replacement
• Air Cleaner Assembly Replacement
• Brake Pressure Modulator Valve (BPMV) Bracket Replacement
• Relay Replacement (Within an Electrical Center)
• Battery Negative Cable Disconnect/Connect Procedure (L26)
• Brake Pedal Assembly Replacement
• Fastener Tightening Specifications
• Fastener Tightening Specifications
• Carpet Replacement - Front
• FASTENER NOTICE
• Communication Interface Module Replacement
• Special Tools
• Refrigerant Recovery and Recharging
• Air Conditioning (A/C) Diagnostics - Pressure Zone A
• Refrigerant System Capacities
• Heating Performance Diagnostic
• Fastener Tightening Specifications
• Heater Hose Replacement - Inlet (LY7)
• Heater Hose Replacement - Outlet (LY7)

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