Hummer H3. Manual — part 1260

abnormal noise?

Go to Step 21

Go to Step 25

15

Verify that the A/C system is properly
charged. Refer to Refrigerant System
Capacities.
Is the A/C system properly charged?

Go to Step 26

Go to Step 16

16

Recharge the A/C system to specification.
Refer to Refrigerant Recovery and
Recharging.
Is the abnormal compressor noise still
present?

Go to Step 24

Go to Step 26

17

Repair the oil leak. Refer to the appropriate
repair procedure for the 3.7L engine.
Is the repair complete?

Go to Step 26

-

18

Replace the drive belt. Refer to Drive Belt
Replacement (Without A/C) or Drive
Belt Replacement (With A/C) .
Is the replacement complete?

Go to Step 26

-

19

Replace the drive belt tensioner. Refer to
Drive Belt Tensioner Replacement .
Is the replacement complete?

Go to Step 26

-

20

Repair or replace the A/C compressor
mounting component.
Is the repair complete?

Go to Step 26

-

21

Repair or replace the component which is
causing the moaning concern as needed.
Is the repair complete?

Go to Step 26

-

22

Correctly route or insulate the A/C
component.
Is the repair complete?

Go to Step 26

-

23

Replace the A/C compressor clutch. Refer
to Compressor Clutch Plate/Hub
Assembly Replacement.
Is the repair complete?

Go to Step 26

-

24

Replace the A/C compressor. Refer to
Compressor Replacement.
Is the repair complete?

Go to Step 26

-

The concern may be caused by an engine
related component. Refer to Vibration

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3

NOISE DIAGNOSIS - HVAC MODULE

Noise Diagnosis - HVAC Module

25

Analysis - Engine .
Did you find and correct the condition?

Go to Step 26

-

26

Operate the system in order to verify the
repair.
Did you find and correct the condition?

System OK

Go to Step 2

Step

Action

Yes

No

DEFINITION: Noise originating from the HVAC module.

1

Were you sent here from Symptoms or
another diagnostic table?

Go to Step 2

Go to
Symptoms -
HVAC Systems
- Manual

2

1. Start the engine.

2. Cycle through all of the following:

Blower motor speeds

HVAC modes

Temperature control settings

3. 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 6

Go to Step 3

3

Is a tick/click, chirping, groaning or
scraping noise present, but decreases as
blower motor speed is decreased?

Go to Step 6

Go to Step 4

4

Is an air rush/whistle noise evident in all
modes but not all temperature settings?

Go to Step 6

Go to Step 5

5

Is an air rush/whistle noise evident only in
defrost or floor mode?

Go to Step 6

Go to Step 6

Remove the instrument panel (I/P)
assembly. Refer to Instrument Panel
Assembly Replacement (Left Hand

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3

ODOR DIAGNOSIS

Odor Diagnosis

6

Drive) or Instrument Panel Assembly
Replacement (Right Hand Drive) .
Is the action complete?

Go to Step 7

-

7

1. Inspect the air flow doors for proper

operation.

2. Inspect the ducts for obstructions or

foreign materials.

Were any of these conditions found?

Go to Step 10

Go to Step 8

8

Inspect the mode and temperature doors
and seals for warping or cracking.
Are the doors in normal condition?

Go to Step 11

Go to Step 9

9

Replace the air distribution case. Refer to
HVAC Module Assembly Replacement
(Left Hand Drive) or HVAC Module
Assembly Replacement (Right Hand
Drive).
Is the repair complete?

Go to Step 11

-

10

Remove any obstructions or foreign
material found.
Is the action complete?

Go to Step 11

-

11

Install the I/P assembly. Refer to
Instrument Panel Assembly
Replacement (Left Hand Drive) or
Instrument Panel Assembly
Replacement (Right Hand Drive) .
Is the action complete?

Go to Step 12

-

12

Operate the system to verify the repair.
Did you find and correct the condition?

System OK

Go to Step 2

Step

Action

Yes

No

DEFINITION: Odor originating or noticed through the HVAC system.

1

Were you sent here from Symptoms or
another diagnostic table?

Go to Step 2

Go to Symptoms
- HVAC Systems
- Manual

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3

2

1. Sit inside the vehicle.

2. Close all of the doors and windows.

3. Start the engine.

4. Allow the engine idle at normal

operating temperature.

5. Select the maximum blower speed.

6. Select the PANEL air outlet mode.

7. Select the coldest temperature

setting.

8. 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 3

Go to Step 8

3

Inspect the HVAC filter and the air inlet
grille for debris.
Is debris present?

Go to Step 4

Go to Step 5

4

Remove any debris.
Is the action complete?

Go to Step 15

-

5

Inspect for wet carpeting.
Is the carpet wet?

Go to Step 6

Go to Step 14

6

Inspect 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 7

Go to Step 14

7

Repair the leak as necessary.
Is the repair complete?

Go to Step 15

-

8

Does the odor have a coolant smell?

Go to Step 9

Go to Step 12

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3