Hummer H2. Manual — part 2031

DTC B1001

Circuit Description

When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) compares the
restraints ID stored in the SDM to the restraints ID stored in the body control module (BCM). The restraints ID
being compared contains the last four digits of the SDM part number. For more detailed information concerning
Class 2 serial data lines, refer to Data Link Communications Description and Operation in Data Link
Communications.

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Action Taken When the DTC Sets

z

The SDM disables all AIR BAG deployments.

z

The SDM commands the AIR BAG indicator ON via Class 2 serial data.

Conditions for Clearing the DTC

z

The condition responsible for setting the DTC no longer exists.

z

You issue a scan tool CLEAR DTCs command.

z

A history DTC will clear once 255 malfunction free ignition cycles have occurred.

Diagnostic Aids

DTC B1001 is an indication that the restraints ID stored in both the BCM and SDM do not match. If either the
BCM or PCM were replaced, the replacement modules need to be reprogrammed for proper operation. In
addition, if the BCM or SDM were replaced, the vehicle theft deterrent (VTD) system will also need to be

Does the DTC reset?

Step

12

System OK

12

1. Turn OFF the ignition.

2. Replace the SDM. Refer to Inflatable Restraint Sensing and

Diagnostic Module Replacement .

Did you complete the replacement?

Go to

Step

13

-

13

1. Turn ON the ignition, with the engine OFF

2. Use the scan tool in order to Clear the DTCs.

3. Operate the vehicle within the Conditions for Running the DTC as

specified in the text.

Does the DTC reset?

Go to

Step

2

System OK

2004 Hummer H2

2004 RESTRAINTS SIR - Hummer H2

reprogrammed.

Test Description

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

2: This step checks to see if the correct VIN is programmed in the PCM.

3: This step explains the proper steps to perform after a PCM has been replaced in order for the PCM to
operate properly.

5: This step explains the proper steps to perform after a BCM has been replaced in order for the BCM to
operate properly.

8: This step explains how to properly program the vehicle theft deterrent (VTD) system.

DTC B1001

Step

Action

Yes

No

Schematic Reference:SIR Schematics
Connector End View Reference:SIR Connector End Views

1

Did you perform the Diagnostic System Check - SIR?

Go to

Step 2

Go to Diagnostic

System Check -

SIR

2

1. Install a scan tool.

2. Turn ON the ignition, with the engine OFF.

3. With a scan tool, verify that the PCM is programmed with the

correct VIN by comparing the VIN that is stored in the PCM to
the VIN plate of the vehicle.

Is the PCM programmed with the correct VIN?

Go to

Step 4

Go to Step 3

3

With a scan tool and/or techline machine, program the correct VIN
into the PCM. Refer to PCM programming in Engine Controls.
Did you complete the programming procedure?

Go to

Step 9

-

4

Was the BCM replaced?

Go to

Step 5

Go to Step 6

5

Program the BCM in order for the BCM to learn the restraints ID from
the SDM. Refer to Body Control Module (BCM)
Programming/RPO Configuration in Body Control System.
Did you complete the programming procedures?

Go to

Step 8

-

6

Was the SDM replaced?

Go to

Step 8

Go to Step 7

7

Replace the SDM. Refer to Inflatable Restraint Sensing and
Diagnostic Module Replacement .
Did you complete the replacement?

Go to

Step 8

-

IMPORTANT:

Use the scan tool to perform the VTD relearn. Do not use the 30
minute manual learn procedure.

2004 Hummer H2

2004 RESTRAINTS SIR - Hummer H2

SYMPTOMS - SIR

Visual/Physical Inspection

z

Inspect for aftermarket devices which could affect the operation of the SIR system. Refer to Checking
Aftermarket Accessories in Wiring Systems.

z

Inspect the easily accessible or visible system components for obvious damage or conditions which could
cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for
Intermittent Conditions and Poor Connections in Wiring Systems.

Symptom List

Refer to Air Bag Indicator Circuit Malfunction in order to diagnose the symptom.

AIR BAG INDICATOR CIRCUIT MALFUNCTION

Circuit Description

The AIR BAG warning lamp is controlled by the inflatable restraint sensing and diagnostic module (SDM) via
Class 2 serial data. When the ignition switch is first turned to the RUN position, the SDM performs tests to

8

Reprogram the vehicle theft deterrent (VTD) system. Refer to
Programming Theft Deterrent System Components in Theft
Deterrent.Did you complete the reprogramming procedure?

Go to

Step 9

-

9

1. Verify that all components, connectors, and CPAs are properly

mounted.

2. Use the scan tool in order to clear the DTCs.

3. Operate the vehicle within the Conditions for Running the DTC

as specified in the supporting text.

Does the DTC reset?

Go to

Step 2

System OK

IMPORTANT: The following steps must be completed before using the Symptom Tables.

1. Perform the Diagnostic System Check - SIR before using the Symptom

Tables in order to verify that all of the following are true:

z

There are no DTCs set.

z

The control module(s) can communicate via the serial data link.

2. Review the system operation in order to familiarize yourself with the

system functions. Refer to SIR System Description and Operation .

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2004 RESTRAINTS SIR - Hummer H2

diagnose critical malfunctions within itself. The SDM then commands the AIR BAG warning lamp OFF after it
has flashed seven times.

Diagnostic Aids

z

If Ignition 1 voltage is outside of the normal operating voltage range (9-16 volts), the AIR BAG warning
lamp will come ON solid with no DTCs set.

z

The loss of serial data communication between the inflatable restraint sensing and diagnostic module
(SDM) and the instrument panel cluster (IPC), will cause the AIR BAG warning lamp to come ON solid.
Refer to DTC U1001-U1254 in Data Link Communications.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

3: This step checks to see if the AIR BAG warning lamp flashes seven times when the ignition switch is
first turned to the RUN position.

4: This step checks to see if DTC U1088 is present in the instrument panel cluster (IPC).

5: This step checks to see if the AIR BAG warning lamp can be commanded ON.

6: This step checks to see if ignition 1 voltage to the SDM is more than 9 V.

7: This step determines if ignition 1 voltage to the SDM is more than 16 V or if there is a malfunctioning
SDM.

8: This step inspects the SDM wiring harness connector for corrosion or damage.

10: Tests for an open or high resistance in the ignition 1 voltage circuit between the SDM and the SIR
Fuse.

12: Tests for an open or high resistance in the ignition 1 voltage circuit to the SIR Fuse.

14: Tests for an open or high resistance in the SDM ground circuit or if there is a malfunctioning SDM.

Air Bag Indicator Circuit Malfunction

Step

Action

Value

(s)

Yes

No

Schematic Reference:SIR Schematics
Connector End View Reference:SIR Connector End Views

1

Did you perform the SIR Diagnostic System
Check?

-

Go to Step 2

Go to Diagnostic

System Check - SIR

2

Did you perform the Instrument Cluster
Diagnostic System Check?

-

Go to Step 3

Go to Diagnostic

System Check -

Instrument Cluster

in Instrument Panel,

Gauges and Console

3

1. Turn OFF the ignition.

2. Observe the AIR BAG warning lamp

while turning the ignition switch to the

-

2004 Hummer H2

2004 RESTRAINTS SIR - Hummer H2