Hummer H2. Manual - part 2025

DIAGNOSTIC INFORMATION AND PROCEDURES 

DIAGNOSTIC STARTING POINT - SIR 

Begin the system diagnosis with Diagnostic System Check - SIR . The Diagnostic System Check - SIR will 
provide the following information: 

z

The identification of the control module(s) which commands the system.  

z

The ability of the control module(s) to communicate through the serial data circuit.  

z

The identification of any stored diagnostic trouble codes (DTCs) and their status.  

The use of Diagnostic System Check - SIR will identify the correct procedure for diagnosing the system and 
where the procedure is located. 

DIAGNOSTIC SYSTEM CHECK - SIR 

These diagnostic procedures will help you to find and repair SIR system malfunctions. This service category 

Connector Part Information

z

54560210  

z

2-Way F Framatone ABX-3 Code C (YE)  

Pin

Wire Color

Circuit No.

Function

A

WH

347

Steering Wheel Module - High Control

B

D-GN

348

Steering Wheel Module - Low Control

CAUTION: Refer to SIR Special Tool Caution in Cautions and Notices.

 

2004 Hummer H2 

2004 RESTRAINTS SIR - Hummer H2

  

also contains information for repairing SIR system malfunctions. For best results, use the diagnostic tables, and 
follow the sequence listed below: 

1. Perform the Diagnostic System Check - SIR. All SIR diagnostics must begin with the A Diagnostic 

System Check - SIR. The Diagnostic System Check - SIR determines the following results: 

z

Proper AIR BAG warning lamp operation  

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Ability of the SDM to communicate through the data link connector (DLC)  

z

Existence of SIR current and/or history diagnostic trouble codes (DTC)  

2. Refer to the diagnostic table as directed by the A Diagnostic System Check - SIR. The diagnostic tables 

will help enable you to diagnose any SIR system malfunction. Bypassing these procedures may result in 
the following problems: 

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Extended diagnostic time  

z

Incorrect diagnosis  

z

Incorrect parts replacement  

3. Repeat the Diagnostic System Check - SIR after you perform any repairs or diagnostic procedures. This 

will verify that you correctly performed the repair. This will also ensure that no other malfunctions exist.  

Test Description 

The numbers below refer to the step numbers on the diagnostic table. 

1: This step checks to see if the AIR BAG warning lamp flashes seven times and then turns off when the 
ignition key is turned ON.  

2: This step checks to see if the scan tool powers up.  

3: This step checks to see if the scan tool can communicate with the inflatable restraint sensing and 
diagnostic module (SDM).  

4: This step checks to see if there are any current or history diagnostic trouble codes (DTCs) present.  

5: This step checks to see if there are communication DTCs (U-codes) present.  

6: This step checks to see if DTC B1000 (ECU Malfunction) is present.  

Diagnostic System Check - SIR 

Step

Action

Yes

No

1

1. Note the AIR BAG 

warning lamp while 
turning the ignition switch 
ON.  

2. The AIR BAG warning 

lamp should turn OFF after 
flashing seven times.  

Does the AIR BAG warning 
lamp flash seven times and then 
turn off?

Go to Step 2

Go to Symptoms - SIR

 

2004 Hummer H2 

2004 RESTRAINTS SIR - Hummer H2

  

SCAN TOOL DATA LIST 

The SIR Scan Tool Data List contains all the restraint system related parameters that are available on the scan 
tool. The parameters in the list are arranged in alphabetical order. The column, "Data List," indicates the 
location of the parameter within the scan tool menu selections. 

Use the SIR Scan Tool Data List as directed by a diagnostic table or in order to supplement the diagnostic 
procedures. Begin all of the diagnostic procedures with the SIR Diagnostic System Check. Use the SIR Scan 
Tool Data List after the following are determined: 

z

There is no published DTC procedure nor published symptom procedure for the customer concern.  

z

The DTC or symptom diagnostic procedure indicated by the diagnostic system check does not resolve the 
customer concern.  

The Typical Data Values are obtained from a properly operating vehicle under the conditions specified in the 
first row of the Scan Tool Data List table. Comparison of the parameter values from the suspect vehicle with the 
Typical Data Values may reveal the source of the customer concern.

2

Install a scan tool. 
Does the scan tool power up?

Go to Step 3

Go to Scan Tool Does Not 

Power Up in Data Link 

Communications

3

Attempt to establish 
communication with the 
inflatable restraint sensing and 
diagnostic module (SDM). 
Does the scan tool communicate 
with the SDM?

Go to Step 4

Go to Scan Tool Does Not 

Communicate with Class 2 

Device in Data Link 

Communications

4

1. Use the scan tool to 

request the SIR diagnostic 
trouble code (DTC) 
display.  

2. Record the displayed DTC

(s) on the repair order, 
specifying as current or 
history.  

Does the scan tool display any 
current or history DTCs?

Go to Step 5

System OK

5

Does the scan tool display any 
DTC's which begin with a "U"?

Go to Scan Tool Does Not 

Communicate with Class 2 

Device in Data Link 

Communications

Go to Step 6

6

Does the scan tool display DTC 
B1000?

Go to DTC B1000 in Body 

Control System

Go to Diagnostic Trouble 

Code (DTC) List

 

2004 Hummer H2 

2004 RESTRAINTS SIR - Hummer H2

  

SIR Scan Tool Data List 

SCAN TOOL DATA DEFINITIONS 

The SIR scan tool data definitions contain a brief description of all SIR related parameters available on the scan 
tool. The parameters that are available on the scan tool are listed below in alphabetical order. 

8 Digit GM Part Number  

The scan tool displays an 8 digit part number. This number is the GM part number that is stored within 
the SDM memory. 

Active Switch  

The scan tool displays enabled or disabled. The signal from the inflatable restraints I/P module disable 
switch indicates whether the passenger frontal air bag is enabled or disabled. 

Calibration ID  

The scan tool displays a 4 digit number. This calibration ID is the check sum of the SDM read only 
memory contents. 

Component Serial Number  

The scan tool displays the digits of the SDM serial number. 

Driver Side Belt Status  

The scan tool displays Buckled or Unbuckled. The signal from the drivers seat belt switch indicates 
whether the driver seat is buckled or unbuckled.

Scan Tool Parameter

Data List

Units Displayed

Typical Data Value

Ignition ON/Engine OFF/Driver Seat Belt Buckled/Active Switch Enabled

8-Digit GM Part Number

Module Information 2

8-digit number

XXXXXXXX

Active Switch

Inputs

Enabled/Disabled

Enabled

Calibration ID

Module Information 1

4-digit number

Varies

Component Serial Number

Module Information 2

4-digit number

XXXX

Driver Side Belt Status

Inputs

Buckled/Unbuckled

Buckled

Electronic Front End Sensor 1 ID

Module Information 1

2-digit number

Varies

Electronic Front End Sensor 2 ID

Module Information 1

2-digit number

Varies

Ignition Voltage

Data

Volts

12 volts

Julian Date of Build

Module Information 1

3-digit number

Varies

ROM ID

Module Information 1

4-digit number

Varies

Year Module Built

Module Information 1

4-digit number

Varies

 

2004 Hummer H2 

2004 RESTRAINTS SIR - Hummer H2