Hummer H2. Manual — part 1431

REPAIR INSTRUCTIONS

POWERTRAIN CONTROL MODULE (PCM) REPLACEMENT

Service of the powertrain control module (PCM) should normally consist of either replacement of the PCM or
electrically erasable programmable read only memory (EEPROM) programming. If the diagnostic procedures
call for the PCM to be replaced, the PCM should be inspected first to see if the correct part is being used. If the
correct part is being used, remove the faulty PCM and install the new service PCM.

z

Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM
module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed
correctly. The gaskets prevent contaminant intrusion into the PCM.

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The replacement PCM must be programmed.

Removal Procedure

Connector Part Information

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15336024

z

2-Way F GT 150 Sealed (BK)

Pin

Wire Color

Circuit No.

Function

1

PU/WH

821

VSS High Signal

2

L-GN/BK

822

VSS Low Signal

IMPORTANT: To prevent internal PCM damage, the ignition must be OFF when

disconnecting or reconnecting power to the PCM. For example, when
working with a battery cable, PCM pigtail, PCM fuse, or jumper cables.

IMPORTANT: It is necessary to record the remaining engine oil life. If the replacement

module is not programed with the remaining engine oil life, the engine oil
life will default to 100%. If the replacement module is not programmed

2004 Hummer H2

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

1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.

Fig. 27: PCM Cover
Courtesy of GENERAL MOTORS CORP.

2. Release the PCM cover mounting holes away from the mounting tabs on the PCM mounting bracket.

3. Release the PCM cover from the mounting bracket.

4. Remove the PCM cover.

with the remaining engine oil life, the engine oil will need to be changed at
5000 km (3,000 mi) from the last engine oil change.

2004 Hummer H2

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

Fig. 28: PCM Harness Connectors
Courtesy of GENERAL MOTORS CORP.

NOTE:

Refer to PCM and ESD Notice in Cautions and Notices.

NOTE:

In order to prevent internal damage to the PCM, the ignition must be OFF
when disconnecting or reconnecting the PCM connector.

2004 Hummer H2

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

5. Loosen both PCM connector retaining bolts.

6. Disconnect the PCM harness connectors.

7. Release the spring latch from the PCM.

8. Release the PCM mounting tabs from the PCM.

Fig. 29: PCM & Engine Compartment
Courtesy of GENERAL MOTORS CORP.

9. Remove the PCM from the engine compartment.

Installation Procedure

2004 Hummer H2

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