HVAC System - Automatic: Removal & Installation Buick LaCrosse II facelift

HVAC Component Replacement Reference

HVAC Component Replacement Reference

HVAC Control Module Replacement

When replacing or disconnecting the HVAC control module, it will be necessary to perform a recalibration process. When installing or reconnecting the HVAC control module, be sure to perform the following

Preferred Method (with Scan Tool)

Note. Do not adjust any controls on the HVAC control module while the HVAC control module is self-calibrating. If interrupted, improper HVAC performance will result.

1. Ignition OFF.
2. Disconnect the scan tool.
3. Install/connect the HVAC control module.
4. Connect all previously disconnected components.
5. Start the vehicle.
6. With the scan tool, initiate the HVAC Actuators Learn feature of the HVAC control module Special Functions menu.
7. Operate system and verify that no DTCs have set as current DTCs.
8. If DTC B101E 4B is set after attempting the actuator recalibration procedure, perform the following: Verify which actuator does not have a scan tool learn status parameter status of complete. Verify the unlearned actuator is physically rotating - A common cause of DTC B101E 4B is an actuator that is electrically OK but fails to physically rotate (e.g. stripped gears). If the unlearned actuator is not physically rotating, replace the actuator, otherwise replace the HVAC control module.

Alternate Method (without Scan Tool)

1. Clear all DTCs.
2. Ignition OFF.
3. Install/connect the HVAC control module.
4. Connect all previously disconnected components.
5. Remove the HVAC control module fuse for a minimum of 10 s.
6. Install the HVAC control module fuse.
7. Start the vehicle.
8. Wait 40 s for the HVAC control module to self-calibrate.

Actuator Replacement

When replacing an HVAC actuator it will be necessary to allow the HVAC control module to perform a recalibration process. When installing an HVAC actuator be sure to perform one of the following

Preferred Method (with Scan Tool)

1. Clear all DTCs.
2. Ignition OFF.
3. Install the HVAC actuator.
4. Connect all previously disconnected components.
5. Start the vehicle.
6. With the scan tool, initiate the HVAC Actuators Relearn feature of the HVAC control module Special Functions menu.
7. Operate system and verify that no DTCs have set as current DTCs.
8. If DTC B101E 4B is set after attempting the actuator recalibration procedure, perform the following: Verify which actuator does not have a scan tool learn status parameter status of complete. Verify the unlearned actuator is physically rotating - A common cause of DTC B101E 4B is an actuator that is electrically OK but fails to physically rotate (e.g. stripped gears). If the unlearned actuator is not physically rotating, replace the actuator, otherwise replace the HVAC control module.

Alternate Method (without Scan Tool)

1. Clear all DTCs.
2. Ignition OFF.
3. Install the HVAC actuator.
4. Connect all previously disconnected components.
5. Remove the HVAC control module fuse for a minimum of 10 s.
6. Install the HVAC control module fuse.
7. Start the vehicle.
8. Wait 40 s for the HVAC control module to self-calibrate.

Scheme 63

Heater and Air Conditioning Remote Control Replacement

Scheme 64

Heater and Blower and Air Conditioning Control Module Replacement

Scheme 65

Mode Valve Lever Replacement

Scheme 66

Vent Valve Lever Replacement

Scheme 67

Air Inlet Valve Actuator Replacement (CJ2)

Scheme 68

Air Inlet Valve Actuator Replacement (Without CJ2)

Scheme 69

Mode Valve Actuator Gear Replacement

Scheme 70

Mode Valve Gear Replacement

Scheme 71

Air Inlet Valve Actuator Gear Replacement

Scheme 72

Air Inlet Valve and Inside Air Valve Control Cam Replacement

Scheme 73

Inside Air Valve Actuator Replacement (CJ2)

Scheme 74

Mode Control Cam Actuator Replacement

Scheme 75

Mode Control Cam Replacement

Removal Procedure

1. Remove the HVAC module from the vehicle. Refer to «Heater and Air Conditioning Evaporator and Blower Module Removal and Installation»(ref-621972-S23089688862014061000000) .
2. Remove the mode cam gear actuator screws (1) and separate the actuator (2) from the HVAC module.
3. Disconnect the mode cam gear actuator electrical connector.
4. Remove the mode cam gear (1) from the HVAC module.
5. For alignment purposes, remove both cam gear levers (2).
6. If the valve gears (3) are damaged, remove them from the HVAC module and discard.

Installation Procedure

1. If the valve gears were removed or replaced, install them onto the HVAC module.
2. Rotate the defroster gear clockwise (1) as far as it will go, and install the lever by engaging a gear tooth into the right most lever gap (2).
3. Rotate the heater door gear clockwise (1) as far as it will go, and install the lever by engaging a gear tooth into the right most lever gap (2).
4. Install the mode cam into position on the levers.
5. Continue to push the mode cam onto the case and rotate left and/or right until an audible click is heard locking the mode cam in place.
6. Rotate the mode cam (1) from stop to stop. It should rotate completely without binding. If the mode cam does not rotate from stop to stop, then remove the mode cam and levers and repeat steps 2-6.
7. Place the mode cam actuator and gear assembly (2) on the HVAC module and install the screws (1).
8. Connect the mode cam actuator electrical connector.
9. Install the HVAC module. Refer to «Heater and Air Conditioning Evaporator and Blower Module Removal and Installation»(ref-621972-S23089688862014061000000) .

Scheme 76

Temperature Valve Actuator Replacement - Right Side

Scheme 77

Temperature Valve Actuator Replacement - Left Side

Scheme 78

Air Conditioning Refrigerant Temperature Sensor Replacement

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Duct Air Temperature Sensor Replacement - Upper Right Side (CJ2)

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Duct Air Temperature Sensor Replacement - Upper Left Side

Scheme 81

Duct Air Temperature Sensor Replacement - Lower Left Side

Scheme 82

Duct Air Temperature Sensor Replacement - Lower Right Side (CJ2)

Scheme 83

Ambient Air Quality Sensor Replacement

Scheme 84

Inside Air Moisture and Windshield Temperature Sensor Replacement

Scheme 85

Sun Load Temperature and Headlamp Automatic Control Ambient Light Sensor Replacement