Hummer H3. Manual — part 589

Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs

Circuit/System Testing

1. With the ignition ON, with a scan tool, request the ignition voltage parameter in the SIR

data list. If the parameter does not read 9-16 volts, test the ignition 1 voltage for a short to
voltage, open/high resistance or a short to ground.

If a condition exists, make the appropriate repair.

2. With the ignition OFF, test the SDM ground circuit for an open or high resistance.

If a condition exists, make the appropriate repair

3. Remove the inflatable restraint SDM connector. Inspect the SDM connector for damage or

corrosion that may cause a malfunction.

If damage or corrosion is found make the appropriate repair.

4. Replace the SDM.

5. If replacement of the SDM does not repair the vehicle, replace the IPC.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

SIR/SRS Wiring Repairs

Control Module References for SDM and IPC replacement, setup and programming

PASSENGER PRESENCE SYSTEM INDICATOR CIRCUIT MALFUNCTION

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Review Strategy Based Diagnosis for an overview of the diagnostic approach.

Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit Description

The PASSENGER AIR BAG ON/OFF indicators located on the instrument panel are used to
notify the driver when the passenger presence system (PPS) has enabled or disabled the
instrument panel (I/P) inflator module. The PPS air bag indicators will also inform the driver of

2007 Hummer H3

2007 RESTRAINTS Supplemental Inflatable Restraints - H3

any PPS malfunctions. When the ignition is turned on, the PPS module is supplied with ignition 1
voltage and commands both PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. The
PPS module conducts tests on the PPS components and circuits while both PASSENGER AIR
BAG ON/OFF indicators are ON. If no malfunctions are detected the PPS module will turn the
PASSENGER AIR BAG indicator ON or OFF depending on the status of the PPS. If a
malfunction is detected, the PPS module will store a DTC, default the PPS to the OFF state and
communicate with the SDM that a DTC has been set. The SDM will request the instrument panel
cluster (IPC) to turn the AIR BAG indicator ON to notify the driver of a PPS malfunction.

Diagnostic Aids

Use this procedure to diagnosis one or both PPS indicators inoperative.

The following can cause an intermittent condition:

A short in the passenger air bag OFF indicator control circuit

A short in the passenger air bag ON indicator control circuit

An open or high resistance in the passenger air bag OFF indicator control circuit

An open or high resistance in the passenger air bag ON indicator control circuit

Reference Information

SIR Schematics

SIR Schematics

Connector End View Reference

SIR Connector End Views

Antilock Brake System Connector End Views

Electrical Information Reference

Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs

Circuit/System Testing

1. With the ignition OFF, Disconnect the inside accessory switch connector. Inspect the

2007 Hummer H3

2007 RESTRAINTS Supplemental Inflatable Restraints - H3

connector for damage or corrosion that may cause a malfunction

If a condition exists, make the appropriate repair.

2. Ignition ON, test the ignition 1 voltage circuit for 9-16 volts. If ignition 1 voltage is not

present, test for an open/high resistance or a short to ground.

If a condition exists, make the appropriate repair.

3. With the ignition OFF, Connect a test lamp between the ignition 1 voltage circuit and the

passenger air bag OFF indicator control circuit at the accessory switch connector terminals.
Ignition ON, test lamp should illuminate.

If the test lamp illuminates, replace the accessory switch.

4. Test the passenger air bag OFF indicator control circuits for a short to ground, open/high

resistance.

If a condition exists, make the appropriate repair

5. Replace the PPS.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Accessory Switch Replacement

SIR/SRS Wiring Repairs

Control Module References for PPS replacement, setup and programming

SIR DISABLING AND ENABLING

SIR component location affects how a vehicle should be serviced. There are parts of the SIR
system installed in various locations around a vehicle. To find the location of the SIR components
refer to SIR Identification Views.

There are several reasons for disabling the SIR system, such as repairs to the SIR system or
servicing a component near or attached to an SIR component. There are several ways to disable
the SIR system depending on what type of service is being performed. The following information
covers the proper procedures for disabling/enabling the SIR system.

SIR Disabling and Enabling

Condition

Action

If the vehicle was involved in an accident
with an air bag deployment.

Disconnect the negative battery cable(s) *.
Refer to Repairs and Inspections Required
After a Collision.

2007 Hummer H3

2007 RESTRAINTS Supplemental Inflatable Restraints - H3

SIR Service Precautions

The inflatable restraint sensing and diagnostic module (SDM) maintains a reserved energy supply.
The reserved energy supply provides deployment power for the air bags if the SDM loses battery
power during a collision. Deployment power is available for as much as 1 minute after
disconnecting the vehicle power. Waiting 1 minute before working on the system after disabling
the SIR system prevents deployment of the air bags from the reserved energy supply.

General Service Instructions

The following are general service instructions which must be followed in order to properly repair
the vehicle and return it to its original integrity:

Do not expose inflator modules to temperatures above 65°C (150°F).

Verify the correct replacement part number. Do not substitute a component from a different
vehicle.

Use only original GM replacement parts available from your authorized GM dealer. Do not
use salvaged parts for repairs to the SIR system.

Discard any of the following components if it has been dropped from a height of 91 cm (3 feet) or
greater:

When performing SIR diagnostics.

Follow the appropriate SIR service manual
diagnostic procedure(s) *

When removing or replacing an SIR
component or a component attached to an
SIR component.

Disconnect the negative battery cable(s) *

If the vehicle is suspected of having shorted
electrical wires.

Disconnect the negative battery cable(s) *

When performing electrical diagnosis on
components other than the SIR system.

Remove the SIR/Airbag fuse(s) when
indicated by the diagnostic procedure to
disable the SIR system

* DTCs will be lost when the negative battery cable is disconnected.

CAUTION: When performing service on or near the SIR components or

the SIR wiring, the SIR system must be disabled. Failure to
observe the correct procedure could cause deployment of the
SIR components. Serious injury can occur. Failure to observe
the correct procedure could also result in unnecessary SIR
system repairs.

2007 Hummer H3

2007 RESTRAINTS Supplemental Inflatable Restraints - H3