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Noise Diagnosis - HVAC Module

WARNING: This page is about a different car, the 2004 Pontiac Vibe. However, it is still accessible from the selected car via links, so may be relevant.
Noise Diagnosis - HVAC Module

Step Action Yes No
DEFINITION: Noise from the HVAC Module.
1 Were you sent here from Symptoms - HVAC Systems - Manual? Go to Step 2  Go to Symptoms - HVAC Systems - Manual
2
  1. Start the engine.
  2. Cycle through all of the following:
    • Blower speeds
    • HVAC modes
    • Temperature settings
  3. Determine the type of noise:
    • Scrape, pop
    • Tick/click, chirp or groaning
    • Air rush/ whistle
Is a noise evident?		 Go to Step 3  -
3 Is a scrape or pop noise evident? Go to Step 7  Go to Step 4 
4 Is a tick/click, chirp or groan noise evident? Go to Step 9  Go to Step 5 
5 Is an air rush/whistle noise evident? Go to Step 6  Go to Step 2 
6 Inspect outlets for proper operation and alignment.
Does everything look normal?		 Go to Step 13  Go to Step 17 
7 Is a scrape or pop noise evident when selecting modes? Go to Step 11  Go to Step 8 
8 Is a scrape or pop noise evident when selecting temperature settings? Go to Step 12  -
9 Remove the passenger compartment air filter. Refer to Passenger Compartment Air Filter Replacement . Inspect the housing for foreign material and/or obstructions.
Was foreign material present?		 Go to Step 15  Go to Step 10 
10 Remove the blower motor. Refer to Blower Motor Replacement .
Inspect the motor and housing for obstructions or foreign material.
Was foreign material present?		 Go to Step 15  Go to Step 11 
11 Visually inspect the mode doors for proper operation while cycling through the mode settings.
Is the linkage properly attached to the mode actuators and doors?		 Go to Step 13  Go to Step 14 
12 Visually inspect the temperature doors for proper operation while cycling through the temperature settings.
Is the linkage properly attached to the temperature actuators and doors?		 Go to Step 13  Go to Step 14 
13
  1. Remove the upper IP. Refer to Trim Pad Replacement - Instrument Panel (I/P) Upper in Instrument Panel, Gages and Console.
  2. Inspect the ducts for obstructions or foreign material.
Was foreign material present?		 Go to Step 15  -
14 Align the linkage to the actuator and the door.
Is the repair complete?		 Go to Step 19  -
15 Remove the obstruction or foreign material.
Is the action complete?		 Go to Step 15  -
16 Align the ducts for proper airflow.
Is the action complete?		 Go to Step 19  -
17 Install the IP Retainer.
Is the action complete?		 Go to Step 19  -
18 Replace the HVAC module. Refer to HVAC Module Assembly Replacement .
Is the repair complete?		 Go to Step 19  -
19 Operate the system to verify the repair.
Did you find and correct the condition?		 System OK Go to Step 2 
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