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Hummer H2. Manual - part 1505

INSPECTION/MAINTENANCE (I/M) SYSTEM DTC TABLE

Inspection/Maintenance (I/M) System DTC Table

INSPECTION/MAINTENANCE (I/M) CATALYST SYSTEM SET PROCEDURE (WITHOUT HP2)

Description

The purpose of this test is to satisfy the enable criteria necessary to execute inspection/maintenance (I/M)

1. Acceleration at part throttle to 75-89

km/h (45-55 mph) with this speed
maintained for 2 minutes.

2. Deceleration to 0 km/h (0 mph).

3. Engine idling for 2 minutes while the

following criteria are maintained:

Service brake depressed

Automatic transmission in drive

Manual transmission in neutral
with the clutch pedal depressed

Is the action complete?

Go to Step 5

Observe the I/M System Status display with a
scan tool.
Did all of the I/M System Status indicators
update to YES?

Go to Step 6

Go to the I/M System Set

Procedure for the systems

that have not updated

Observe the emission related DTC portion of
the I/M System Status display with a scan tool.
Does the scan tool indicate any emission
related DTCs set?

Go to

Diagnostic

Trouble

Code (DTC)

List

System OK

System

DTCs Required to Set System Status to YES

Catalyst

DTC P0420 or P0430

EVAP

DTC P0455
DTC P0442
DTC P0446
DTC P0496

Oxygen Sensor

DTC P0133 or P0153
DTC P0140 or P0160
DTC P1133 or P1153
DTC P1134 or P1154
DTC P0136 or P0156

Oxygen Sensor Heater

DTC P0135 or P0155

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls (Troubleshooting) - 4.8L, 5.3L, and 6.0L - Hummer H2

readiness diagnostics for the catalyst system. The test may be used to set the I/M System Status indicators to
YES. The I/M System Status display on the scan tool provides an indication of whether the control module has
completed the required tests. The I/M System Status does not indicate that the tests have passed or failed. When
all of the diagnostics for a specific system have run and passed, the I/M System Status will update to YES. If a
test for a specific system has failed, the I/M System Status will update to YES, indicating a determination was
made even if all of the other tests for that system have not run.

Conditions for Running

The engine load must be stable.

DTCs P0420 and P0430 are not set.

The barometric pressure is more than 74 kPa.

The engine coolant temperature (ECT) is between 70-120°C (158-248°F).

The engine has been running for more than 10 minutes.

The engine is in Closed Loop fuel control.

The battery voltage is more than 10-18 volts.

The intake air temperature (IAT) is between -7 and +85°C (+20 and +185°F).

The difference between the engine speed and the desired engine speed is less than 200 RPM.

Diagnostic Aids

The control module runs a calibrated number of catalyst tests per trip until the Catalyst System Status updates to
YES. If the status does not update, the test outlined in this procedure can be repeated until the I/M System
Status updates to YES.

If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the
set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan
tool data list and the service information for an indication of why the test does not complete. Some tests may
abort due to changes in the conditions while the test is running. For example, changes in engine load such as a
cooling fan or A/C compressor clutch turning ON may cause the test to abort.

Inspection/Maintenance (I/M) Catalyst System Set Procedure (Without HP2)

Step

Action

Yes

Did you perform the Inspection/Maintenance (I/M)
System Check?

Go to Step 2

Go to

Inspection/Maintenance

(I/M) System Check

1. Ensure the vehicle is within the Conditions

for Running specified in the supporting text.

2. Turn OFF all of the accessories, e.g., A/C,

blower fan, etc.

3. Start the engine and allow it to idle for 2

minutes.

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls (Troubleshooting) - 4.8L, 5.3L, and 6.0L - Hummer H2

4. Observe the I/M System Status display with

a scan tool.

Did the catalyst System Status update to YES?

CAUTION:

Refer to Road Test Caution in Cautions
and Notices.

IMPORTANT:

In order for this test to run, the vehicle
must operate in the following conditions:

Acceleration at part throttle to 90
km/h (55 mph) with this speed
maintained for 8 minutes

Deceleration to 0 km/h (0 mph)

Engine idling for 2 minutes while the
following criteria is maintained:

{

Service brake depressed

{

Automatic transmission in
Drive

Go to Step 5

Go to Step 3

Observe the DTC Information with a scan tool.
Does the scan tool indicate any failed DTCs?

Go to

Diagnostic

Trouble Code

(DTC) List

Go to Step 4

1. Refer to the Inspection/Maintenance (I/M)

System DTC Table to determine which
DTCs are required to run in order to
complete this test.

2. Observe the Not Ran Since Code Cleared

display with a scan tool.

3. Determine which of the DTCs required for a

YES status has not run.

4. Enter the DTC number in the specific DTC

menu of the scan tool.

5. Operate the vehicle within the Conditions

for Running the DTC, located in the
supporting text for the diagnostic table of the
DTC.

6. Repeat the procedure until the scan tool

indicates the diagnostic test has run.

7. Repeat steps 4-6 for any additional required

DTCs that have not run.

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls (Troubleshooting) - 4.8L, 5.3L, and 6.0L - Hummer H2

INSPECTION/MAINTENANCE (I/M) EVAPORATIVE EMISSION (EVAP) SYSTEM SET
PROCEDURE

Description

The purpose of this test is to satisfy the enable criteria necessary in order to execute the inspection/maintenance
(I/M) readiness diagnostics for the evaporative emission (EVAP) system. The test may be used in order to set
the I/M System Status indicators to YES. The I/M System Status Display on the scan tool provides an indication
of when the control module has completed the required tests. The I/M System Status does not indicate that the
tests have passed or failed. When all of the diagnostics for a specific system have run and passed and I/M
System Status will update to YES. If a test for a specific system has failed, the I/M System Status will update to
YES, indicating a determination was made, even if all of the other tests for that system have not run. Performing
a visual inspection prior to running the EVAP test may prevent having to repeat the test. A failed or aborted test
will require the vehicle to cool down in order to meet the enable criteria to run another test.

Conditions for Running

DTCs P0442, P0446, P0455, P0496 are not set.

The barometric pressure (BARO) is more than 75 kPa.

The fuel level is between 1/4 and 3/4.

The battery voltage is between 10-18 volts.

The engine coolant temperature (ECT) is between 3.75-30°C (39-86°F).

The intake air temperature (IAT) is between 3.75-30°C (39-86°F).

The difference between the ECT and the IAT is less than 8°C (14°F).

Diagnostic Aids

If there is an impending failure, the system may require more time to run the diagnostic than was allotted in the
set procedure. If the test does not run after numerous attempts and no DTC is set, review the appropriate scan
tool data list and the service information for an indication of why the test does not complete. Some tests may
abort due to changes in the conditions while the test is running. For example, changes in engine load such as
cooling fan or an A/C compressor clutch turning ON may cause the test to abort.

Inspection/Maintenance (I/M) Evaporative Emission (EVAP) System Set Procedure

8. Observe the I/M System Status display with

a scan tool.

Did the catalyst System Status update to YES?

Go to Step 5

Go to Diagnostic Aids

Observe the emission related DTC portion of the
I/M System Status display with a scan tool.
Does the scan tool indicate any emission related
DTCs set?

Go to

Diagnostic

Trouble Code

(DTC) List

System OK

Step

Action

Yes

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls (Troubleshooting) - 4.8L, 5.3L, and 6.0L - Hummer H2

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