Hummer H3. Manual — part 1259

NOISE DIAGNOSIS - BLOWER MOTOR

Noise Diagnosis - Blower Motor

12

Heating Performance Diagnostic.
Is the repair complete?

Go to Step 15

-

13

Repair the A/C performance concern. Refer
to Air Conditioning (A/C) System
Performance Test.
Is the repair complete?

Go to Step 15

-

14

Repair the recirculation door concern.
Refer to Air Recirculation Malfunction .
Is the repair complete?

Go to Step 15

-

15

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 blower motor.

1

Were you sent here from Symptoms or
another diagnostic table?

Go to Step 2

Go to

Symptoms -

HVAC Systems

- Manual

2

Inspect the air inlet grille for debris.
Is debris present?

Go to Step 8

Go to Step 3

3

1. Sit inside the vehicle.

2. Close the vehicle doors and

windows.

3. Turn ON the ignition, with the engine

OFF.

4. Cycle the blower motor through all

of the speeds and modes in order to
determine where and when the noise
occurs.

Is a noise evident during the blower
operation?

Go to Step 4

Go to Step 11

Inspect for excessive vibration at each
blower motor speed by feeling the blower

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3

4

case.
Is excess vibration present?

Go to Step 6

Go to Step 5

5

Listen to the blower motor at each speed.
Is the blower motor making a squeaking or
chirping noise?

Go to Step 9

Go to Step 11

6

1. Remove the blower motor. Refer to

Blower Motor Replacement (Left
Hand Drive) or Blower Motor
Replacement (Right Hand Drive).

2. Inspect the blower motor impeller for

deposits of foreign material.

3. 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 8

Go to Step 7

7

Inspect 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 9

Go to Step 10

8

Remove the foreign material.
Is the action complete?

Go to Step 10

-

9

Replace the blower motor. Refer to
Blower Motor Replacement (Left Hand
Drive) or Blower Motor Replacement
(Right Hand Drive).
Is the repair complete?

Go to Step 11

-

10

Install the blower motor. Refer to Blower
Motor Replacement (Left Hand Drive)
or Blower Motor Replacement (Right
Hand Drive).
Is the action complete?

Go to Step 11

-

Operate the system in order to verify the

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3

NOISE DIAGNOSIS - AIR CONDITIONING (A/C) SYSTEM

Noise Diagnosis - Air Conditioning (A/C) System

11

repair.
Did you find and correct the condition?

System OK

Go to Step 2

Step

Action

Yes

No

DEFINITION: Noise originating from the A/C compressor, drive belt or the A/C lines.

1

Were you sent here from Symptoms or
another diagnostic table?

Go to Step 2

Go to
Symptoms -
HVAC Systems
- Manual

2

1. A/C system noises can be generally

categorized into three areas:

Screeching, Squealing, Chirping
noises

Moaning noises

Vibration/Rattle noises

2. Start the engine.

3. Ensure that the A/C is ON.

Is a screeching, squealing noise heard when
the A/C is engaged?

Go to Step 3

Go to Step 9

3

With the engine OFF, inspect the drive belt
for excessive wear. Refer to Drive Belt
Falls Off and Excessive Wear Diagnosis .
Is the drive belt excessively worn?

Go to Step 18

Go to Step 4

4

Inspect the drive belt tension. Refer to
Drive Belt Tensioner Diagnosis .
Is the drive belt tension correct?

Go to Step 5

Go to Step 19

5

Inspect the drive belt for excessive oil
coverage.
Is the drive belt covered with oil?

Go to Step 17

Go to Step 6

6

1. Start the engine.

2. Ensure that the A/C is ON.

3. Inspect the compressor and the clutch.

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3

Is the A/C compressor locked up?

Go to Step 24

Go to Step 7

7

Is the A/C compressor clutch slipping?

Go to Step 23

Go to Step 8

8

Using a stethoscope, listen to the A/C
compressor for any abnormal noises.Is the
compressor causing an abnormal noise?

CAUTION:

Refer to MOVING PARTS AND HOT SURFACES
CAUTION .

Go to Step 15

Go to Step 10

9

Does a moaning noise exist when the A/C
clutch is engaged?

Go to Step 10

Go to Step 12

10

Listen 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 20

Go to Step 11

11

1. Idle the engine.

2. Engage the A/C compressor clutch.

3. Using a stethoscope, move around the

entire refrigerant plumbing system.
Listening 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 22

Go to Step 13

12

Does a vibration or rattle noise exist when
the A/C clutch is engaged?

Go to Step 13

Go to Step 14

13

Does the noise stop when the A/C clutch is
disengaged?

Go to Step 15

Go to Step 25

14

1. Idle the engine in PARK with the A/C

compressor clutch engaged.

2. 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

2007 Hummer H3

2007 HVAC Heating, Ventilation and Air Conditioning - H3