Hummer H3. Manual — part 1299

6

3. Place the recirculation switch in the

ON position.

4. Observe the recirculation door.

5. Place the outside air switch in the

ON position.

Does the recirculation door move from the
recirculation to the outside air position?

Go to Step 7

Go to Air
Recirculation
Malfunction

7

1. Place the blower motor switch in the

maximum speed position.

2. Place the mode switch in each mode

position.

Does air flow sufficiently from the proper
air distribution outlets for each selected
mode position?

Go to Testing
for Intermittent
Conditions and
Poor
Connections

Go to Step 8

8

Inspect the air delivery system for the
following conditions:

A dirty HVAC air filter, if
applicable

An obstruction to the airflow

Air leaks

Misaligned air ducts

Did you find and correct the condition?

Go to Step 21

Go to Step 9

9

Inspect the mode door and the mode
actuator for the following conditions:

A misaligned mode actuator-Refer to
Mode Actuator Replacement
(Left Hand Drive) or Mode
Actuator Replacement (Right
Hand Drive).

Broken or binding linkages or mode
door

2007 Hummer H3

2007 HVAC HVAC - Manual - H3

An obstruction that prevents the
mode actuator from operating within
the full range of motion

Missing seals to the mode door

Misaligned seals to the mode door

Did you find and correct the condition?

Go to Step 21

Go to Step 10

10

Test the position signal circuit of the mode
actuator for an open or for a high
resistance. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 11

11

Test the low reference circuit of the mode
actuator for an open or for a high
resistance. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 12

12

Test the 5-volt reference circuit of the
appropriate mode actuator for an open or
for a high resistance. Refer to Circuit
Testing and Wiring Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 13

13

1. Turn OFF the ignition.

2. Reconnect the mode actuator.

3. Turn ON the ignition with the engine

OFF.

4. Connect a test lamp between mode

door control A and mode door
control B circuits of the mode
actuator connector.

5. Place the mode switch in the Defrost

position.

6. Place the mode switch in the Panel

position.

Does the test lamp illuminate in both

2007 Hummer H3

2007 HVAC HVAC - Manual - H3

positions?

Go to Step 17

Go to Step 14

14

Test the mode door control A and mode
door control B circuits of the mode
actuator for an open, a high resistance, a
short to ground or a short to voltage. Refer
to Circuit Testing and Wiring Repairs .
Did you find and correct the condition ?

Go to Step 21

Go to Step 18

15

Test the voltage circuits of the HVAC
control assembly for an open or for a high
resistance. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 16

16

Test the ground circuit of the HVAC
control assembly for an open or for a high
resistance. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 18

17

Inspect for bad connections at the harness
connector of the mode actuator. Refer to
Testing for Intermittent Conditions
and Poor Connections and Connector
Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 19

18

Inspect for bad connections at the harness
connector of the HVAC control assembly.
Refer to Testing for Intermittent
Conditions and Poor Connections and
Connector Repairs .
Did you find and correct the condition?

Go to Step 21

Go to Step 20

19

Replace the mode actuator. Refer to Mode
Actuator Replacement (Left Hand
Drive) or Mode Actuator Replacement
(Right Hand Drive).
Did you complete the replacement?

Go to Step 21

-

20

Replace the HVAC control assembly.
Refer to Heater and Air Conditioning
Control Replacement.
Did you complete the replacement?

Go to Step 21

-

2007 Hummer H3

2007 HVAC HVAC - Manual - H3

AIR RECIRCULATION MALFUNCTION

Test Description

The number below refers to the step number on the diagnostic table.

5: This step tests the HVAC control assemblies ability to reverse the polarity of the door
control A and door control B circuits. The test lamp should illuminate.

Air Recirculation Malfunction

21

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

System OK

Go to Step 8 .

Step

Action

Yes

No

Schematic Reference: HVAC Schematics
Connector End View Reference: HVAC Connector End Views
DEFINITION: Air recirculation is inoperative or is always ON.

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to Step 2

Go to
Diagnostic
System Check -
Vehicle

2

1. Turn the ignition ON, with the

engine OFF.

2. Place the blower motor switch to the

low speed position.

3. Place the mode switch in the vent

position.

4. Lower the glove box off its upper

attachments.

5. Place the recirculation switch in the

ON position.

6. Observe the recirculation door.

7. Place the recirculation switch in the

OFF position.

Does the recirculation door move from the
recirculation to the outside air position?

Go to Testing
for Intermittent
Conditions and
Poor
Connections

Go to Step 3

2007 Hummer H3

2007 HVAC HVAC - Manual - H3