Supplemental Inflatable Restraint System Buick LaCrosse I

Fastener Tightening Specifications

Fastener Tightening Specifications

SIR Schematic Icons

SIR Schematic Icons Icon Icon Definition CAUTION: When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling Zones in SIR Disabling and Enabling Zones . Failure to observe the correct procedure could cause deployment of the SIR components, personal injury or unnecessary SIR system repairs. IMPORTANT: In order to prevent accidental deployment, the shorting bars close in order to short the connectors when the connectors are separated. Twisted-pair wires provide an effective shield that helps protect sensitive electronic components from electrical interference. If the wires were covered with shielding, install new shielding. In order to prevent electrical interference from degrading the performance of the connected components, you must maintain the proper specification when making any repairs to the twisted-pair wires shown : The wires must be twisted a minimum of 9 turns per 31 cm (12 in) as measured anywhere along the length of the wires The outside diameter of the twisted wires must not exceed 6.0 mm (0.25 in)

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SIR Zone Identification Views

The SIR Zone Identification Views shown below illustrate the approximate location of all SIR components available for the vehicle. This will assist in determining the appropriate SIR Disabling and Enabling Zones for a given service procedure, refer to SIR Disabling and Enabling Zones .

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SIR Connector End Views

Inflatable Restraint Passenger Air Bag ON/OFF Indicator Connector Part Information OEM: 15398877 (Delphi) HCMPB-05-S (JST) Service: See Catalog 5-Way F HCM (NA) Pin Wire Color Circuit No. Function 1 D-BU 2307 Passenger Air Bag On Indicator Control 2 BK/WH 1551 Ground 3 D-GN 2308 Passenger Air Bag Off Indicator Control 4 YE 1139 Ignition 1 Voltage 5 PU 5234 Passenger Seat Belt Indicator

Inflatable Restraint Front End Sensor - Left Connector Part Information OEM: Assembly 15356724 Connector 15369264 PLR 12191733 Connector Seal 12191884 Service: 15306418 2-Way F GT 150 Series Sealed (YE) Pin Wire Color Circuit No. Function A GY 2260 Low Reference B YE 2160 Front End Sensor Signal - Left

Inflatable Restraint Front End Sensor - Right Connector Part Information OEM: Assembly 15356724 Connector 15369264 PLR 12191733 Connector Seal 12191884 Service: 15306418 2-Way F GT 150 Series Sealed (YE) Pin Wire Color Circuit No. Function A PU 2612 Low Reference B WH/BK 2611 Front End Sensor Signal - Right Front

Inflatable Restraint Front Passenger Presence System (PPS) Module C1 Connector Part Information OEM: 15466034 (Delphi) MX12010553 (JAE) Service: See Catalog 10-Way F Type 3 Socket Housing (BK) Pin Wire Color Circuit No. Function 1 OG 640 Battery Positive Voltage 2 YE 1139 Ignition 1 Voltage 3 D-BU 2307 Passenger Air Bag On Indicator Control 4 D-GN 2308 Passenger Air Bag Off Indicator Control 5 PK 2306 Occupant Sensor Serial Data Link 6 BK/WH 1751 Ground 7-9 - - Not Used 10 D-BU 2479 Passenger Heated Seat Element Supply Voltage (KA1)

Inflatable Restraint Front Passenger Presence System (PPS) Module C2 Connector Part Information OEM: SJ101416 (JAE) Service: See Catalog 14-Way F (BK) Pin Wire Color Circuit No. Function A1 WH 783 Temperature Sensor A2 RD 783 Humidity Sensor A3 YE 783 Ground A4 L-GN 783 Ignition 1 Voltage B1 GY 733 Front Passenger Mass and Position Signal B2 GY 744 Front Passenger Mass and Position Signal B3 GY 803 Front Passenger Mass and Position Signal B4 GY 872 Front Passenger Mass and Position Signal B5 GY 878 Front Passenger Mass and Position Signal B6 GY 1004 Front Passenger Mass and Position Signal B7 GY 1068 Front Passenger Mass and Position Signal B8 GY 1073 Front Passenger Mass and Position Signal B9-B10 - - Not Used

Inflatable Restraint I/P Module C1 Connector Part Information OEM: CA-252-92-4-R (AMP) Service: See Catalog 2-Way F (GY) Pin Wire Color Circuit No. Function 1 YE 3025 I/P Module - Stage 1 - High Control 2 OG 3024 I/P Module - Stage 1 - Low Control

Inflatable Restraint I/P Module C2 Connector Part Information OEM: CA-252-92-5-Q (AMP) Service: See Catalog 2-Way F (PU) Pin Wire Color Circuit No. Function 1 GY 3027 I/P Module - Stage 2 - High Control 2 PU 3026 I/P Module - Stage 2 - Low Control

Inflatable Restraint Roof Rail Module - Left (AY1) Connector Part Information OEM: 15454450 (AMP) Service: See Catalog 2-Way F 90 Degree Lockable Squib (YE) Pin Wire Color Circuit No. Function 1 BN 2137 Roof Rail Module - LF - High Control 2 YE/BK 2138 Roof Rail Module - LF - Low Control

Inflatable Restraint Roof Rail Module - Right (AY1) Connector Part Information OEM: 15454451 (AMP) Service: See Catalog 2-Way F 90 Degree Lockable Squib (YE) Pin Wire Color Circuit No. Function 1 BK/WH 2135 Roof Rail Module - RF - High Control 2 L-GN 2136 Roof Rail Module - RF - Low Control

Inflatable Restraint Sensing and Diagnostic Module (SDM) Connector Part Information OEM: 15357038 Service: See Catalog 34-Way F Micro-Pack 100W Series Sealed (GY) Pin Wire Color Circuit No. Function A1 TN 3021 Steering Wheel Module - Stage 1 - High Control A2 BN 3020 Steering Wheel Module - Stage 1 - Low Control A3 OG 3024 I/P Module - Stage 1 - Low Control A4 YE 3025 I/P Module - Stage 1 - High Control A5 BK/WH 2118 Seat Belt Pretensioner - Left - High Control A6 OG/BK 2119 Seat Belt Pretensioner - Left - Low Control A7 OG 2117 Seat Belt Pretensioner - Right - Low Control A8 L-GN 2116 Seat Belt Pretensioner - Right - High Control A9 BK/WH 1751 Ground A10 YE 1139 Ignition 1 Voltage A11 D-BU 1128 SDM Class 2 Serial Data A12 - - Not Used A13 PK 2306 Occupant Sensor Serial Data Link A14 BK/WH 238 Seat Belt Switch - Left A15 - - Not Used A16 RD 1362 Seat Belt Switch - Right - Signal A17-A18 - - Not Used B1 WH 3023 Steering Wheel Module - Stage 2 - High Control B2 PK 3022 Steering Wheel Module - Stage 2 - Low Control B3 PU 3026 I/P Module - Stage 2 - Low Control B4 GY 3027 I/P Module - Stage 2 - High Control B5 YE 2160 Front End Sensor Signal - Left B6 GY 2260 Low Reference B7 PU 2612 Low Reference B8 WH/BK 2611 Front End Sensor Signal - Right Front C1 BN 2137 Roof Rail Module - LF - High Control (AY1) C2 YE/BK 2138 Roof Rail Module - LF - Low Control (AY1) C3 L-GN 2136 Roof Rail Module - RF - Low Control (AY1) C4 BK/WH 2135 Roof Rail Module - RF - High Control (AY1) C5 YE 2131 Side Impact Sensing Module - Left - Voltage (AY1) C6 WH 2132 Side Impact Sensing Module - Left - Signal (AY1) C7 D-GN 2134 Side Impact Sensing Module - Right - Signal (AY1) C8 TN 2133 Side Impact Sensing Module - Right - Voltage (AY1)

Inflatable Restraint Side Impact Sensor - Left (AY1) Connector Part Information OEM: Assembly 15356723 Connector 15369264 PLR 15304620 Connector Seal 12191884 Service: 15306418 2-Way F GT 150 Series (YE) Pin Wire Color Circuit No. Function A WH 2132 Side Impact Sensing Module - Left - Signal B YE 2131 Side Impact Sensing Module - Left - Voltage

Inflatable Restraint Side Impact Sensor - Right (AY1) Connector Part Information OEM: Assembly 15356723 Connector 15369264 PLR 15304620 Connector Seal 12191884 Service: 15306418 2-Way F GT 150 Series (YE) Pin Wire Color Circuit No. Function A D-GN 2134 Side Impact Sensing Module - Right - Signal B TN 2133 Side Impact Sensing Module - Right - Voltage

Inflatable Restraint Steering Wheel Module C1 Connector Part Information OEM: CA-252-92-4-R (AMP) Service: See Catalog 2-Way F (GY) Pin Wire Color Circuit No. Function 1 TN 3021 Steering Wheel Module - Stage 1 - High Control 2 BN 3020 Steering Wheel Module - Stage 1 - Low Control

Inflatable Restraint Steering Wheel Module C2 Connector Part Information OEM: CA-252-92-5-Q (AMP) Service: See Catalog 2-Way F (PU) Pin Wire Color Circuit No. Function 1 WH 3023 Steering Wheel Module - Stage 2 - High Control 2 PK 3022 Steering Wheel Module - Stage 2 - Low Control

Seat Belt Pretensioner - Left Connector Part Information OEM: 12186799 Service: 15306012 2-Way M Metri-Pack 280 Series (YE) Pin Wire Color Circuit No. Function A BK/WH 2118 Seat Belt Pretensioner - Left - High Control B OG/BK 2119 Seat Belt Pretensioner - Left - Low Control

Seat Belt Pretensioner - Right Connector Part Information OEM: 12186799 Service: 15306012 2-Way M Metri-Pack 280 Series (YE) Pin Wire Color Circuit No. Function A L-GN 2116 Seat Belt Pretensioner - Right - High Control B OG 2117 Seat Belt Pretensioner - Right - Low Control

DIAGNOSTIC CODE INDEX

DIAGNOSTIC CODE INDEX

Diagnostic Starting Point - SIR

Begin the system diagnosis with the Diagnostic System Check - Vehicle in Vehicle DTC Information. The Vehicle System Check will provide the following information

1. The identification of the control module(s) which commands the system
2. The ability of the control module(s) to communicate through the serial data circuit
3. The identification of any stored diagnostic trouble codes (DTCs) and their status

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

Introduction

When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. When the SDM has completed the power-up mode the SDM will establish communication with the Passenger Presence System (PPS). The PPS will respond by performing diagnostic tests to check for proper circuit continuity and for shorts to ground and voltage within the PPS. If the PPS detects a malfunction, the PPS will set a DTC, then communicate through a non class 2 communications circuit to the SDM that a malfunction has occurred, while turning the passenger air bag status indicator to OFF. The SDM will respond by disabling the instrument panel (I/P) module deployment loop, setting either DTC B0092 or DTC B0098 and commanding the AIR BAG indicator ON. The SDM notify the driver of a PPS or SIR malfunction by turning ON the AIR BAG indicator on the cluster. The DTCs that the PPS set are non class 2 and have to be flashed through the PASSENGER AIR BAG ON/OFF indicators. The procedures below are designed to assist in the flashing of these codes. Before you start, read these procedures carefully and completely. For further information regarding the PPS refer to SIR System Description and Operation .

Passenger Presence System (PPS) Flash Code Procedure

1. Empty the front outboard passenger seat.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, request the PPS to flash DTCs.
5. When the PPS receives a valid request to flash DTCs, the PPS will perform the following: Illuminate both PASSENGER AIR BAG ON and OFF indicators for 1 second. Turn OFF both PASSENGER AIR BAG ON and OFF indicators for 1 second. Flash the first number of the DTC using the OFF indicator. This will be an ODD number. Count the number of times the OFF indicator flashes to obtain the first number of the DTC. Flash the second number of the DTC using the ON indicator. This will be an Even number. Count the number of times the ON indicator flashes to obtain the second number of the DTC. When the flashing procedure is initiated, to determine if a code is current or history, the PPS will flash current DTCs two times consecutively and flash history DTCs once.
6. If the flashing procedure was unsuccessful repeat this procedure. Due to the communication status between the SDM and the PPS module, this procedure may have to be repeated until a successful flashing attempt has been achieved.
7. Refer to the «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information__diagnostic-trouble-code-dtc-list) in Vehicle DTC Information, to diagnose the DTCs you have obtained.

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 Diagnostic System Check - SIR. Use the SIR Scan Tool Data List after the following is determined

1. There is no published diagnostic trouble code (DTC) procedure nor published symptom procedure for the customer concern.
2. 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 second 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.

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.

Diagnostic Fault Information

Circuit/System Description

The inflatable restraint Passenger Presence System (PPS) is a calibrated unit. Anytime the passenger seat bottom cushion or trim attachments have been removed/serviced or the PPS has been replaced, the PPS system must learn the empty seat value by rezeroing. If there is an error during the rezeroing process, the PPS will set DTC 032. DTC 056 will also set indicating a system fault until a successful rezero has been completed. When the PPS detects this DTC within the PPS it will notify the customer of the enable/disable status by turning on the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators, then the PPS will communicate to the sensing and diagnostic module (SDM) through a non class 2 communications circuit that a PPS fault is present. The SDM will then turn the AIR BAG indicator ON and set DTC B0092 indicating a problem within the PPS and will suppress the deployment of the instrument panel (I/P) module.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

1. An error occurs after a rezero command was given.
2. Sensor data is out of range during rezero.

Action Taken When the DTC Sets

1. The PPS will set a DTC 032 and then communicate with the SDM via non class 2 circuit.
2. The PPS will also set DTC 056 indicating a PPS internal system fault has occurred until the re-zeroing procedure was performed.
3. The SDM will set DTC B0092.
4. The SDM disables the I/P module deployment loop.
5. The PPS will turn ON the passenger air bag status OFF indicator.
6. The SDM commands the AIR BAG indicator ON via serial data communications.

Conditions for Clearing the DTC

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

Diagnostic Aids

This fault indicates that the system did not correctly rezero. You may have to perform the rezero process several times until an acceptable rezero is achieved. When the PPS has been properly rezeroed, using a scan tool a clear DTCs command must be given to clear DTC 032 and DTC 056 from history.

Schematic Reference

SIR Schematics

Connector End View Reference

SIR Connector End Views

Electrical Information Reference

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

Circuit/System Testing

1. Ignition ON, use the scan tool. Use the scan tool to clear all SIR and PPS DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Rezero the PPS, refer to «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 032 exist.
2. Replace the PPS if DTC 032 reset.

Repair Instructions

Control Module References for SDM and PPS replacement, setup and programming.

The inflatable restraint Passenger Presence System (PPS) has several flexible conductive metal strips placed underneath the seat cushion trim. These sensor strips transmit and receive a low-level electric field. If the seat is saturated with liquid, the PPS will detect a low resistance value between these sensor strips. If this occurs, allow seat to dry and check if fault returns. If the PPS determines there is a wet seat condition the PPS will communicate to the sensing and diagnostic module (SDM) through a non class 2 communications circuit that a PPS fault is present. When the PPS detects this DTC within the PPS it will notify the customer of the enable/disable status by turning on the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators, then the PPS will communicate to the SDM that a PPS fault is present. The SDM will then turn the AIR BAG indicator ON and set DTC B0092 indicating a problem within the PPS and will suppress the deployment of the instrument panel (I/P) module. In some conditions DTC 056 will set along with DTC 034. The wet seat fault should be diagnosed first.

Ignition voltage is between 9-16 volts.

1. Seat or seat trim/foam is saturated with liquid.
2. Low resistance values between sensor strips.

1. The PPS will set a DTC 034 and then communicate with the SDM via non class 2 circuit.
2. The PPS will also set DTC 056 indicating a PPS internal system fault has occurred until the re-zeroing procedure was performed.
3. The SDM will set DTC B0092.
4. The SDM disables the I/P module deployment loop.
5. The PPS will turn ON the passenger air bag status OFF indicator.
6. The SDM commands the AIR BAG indicator ON via serial data communications.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

This fault indicates that the seat or seat trim/foam is saturated with liquid. If this DTC sets, verify the wet seat condition, let dry and see if fault returns. If DTC 056 is set along with DTC 034, diagnose the wet seat fault first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool. Use the scan tool to clear all SIR and PPS DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Rezero the PPS, refer to «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 034 exist.
2. Remove the PPS and passenger seat bottom cushion assembly and allow to air dry (approximately 24 hours). Reinstall the PPS and seat bottom cushion assembly. Note: refer to «Inflatable Restraint Passenger Presence System Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in repair instructions.
3. Ignition ON, use the scan tool. Use the scan tool to clear all SIR and PPS DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Rezero the PPS, refer to «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 034 exist.
4. Replace the PPS if DTC 034 reset.

Control Module References for SDM and PPS replacement, setup and programming.

The inflatable restraint Passenger Presence System (PPS) continuously monitors itself for critical faults. If the PPS determines that there is a communication fault or battery voltage has fallen below a threshold causing a communication fault, the PPS will set DTC 036, turn the passenger air bag status indicator to OFF. Then the PPS will try to communicate with the sensing and diagnostic module (SDM) through a non class 2 communications circuit that a PPS fault is present. The SDM will then turn the air bag indicator to ON and set DTC B0092 indicating a problem within the PPS and will suppress the deployment of the instrument panel (I/P) module.

Ignition voltage is between 9-16 volts.

1. The PPS has lost communications with the SDM.
2. The PPS receives incorrect messages.
3. The SDM has lost or receive no communications with the PPS.
4. Battery voltage outside the range of 8-18 volts.

1. The PPS will set a DTC 036 and then communicate with the SDM via non class 2 circuit.
2. The PPS will also set DTC 056 indicating a PPS internal system fault has occurred until the re-zeroing procedure was performed.
3. The SDM will set DTC B0092.
4. The SDM disables the I/P module deployment loop.
5. The PPS will turn ON the passenger air bag status OFF indicator.
6. The SDM commands the AIR BAG indicator ON via serial data communications.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

This fault indicates that there is either a communication or battery voltage problem.

SIR Schematics

1. «SIR Connector End Views»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__sir-connector-end-views)
2. «Power Seat Systems Connector End Views»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system)

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool. Go to the PPS menu, then retrieve the DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 036 is set.
2. Ignition OFF, disconnect the PPS module connector. Refer to «Inflatable Restraint Passenger Presence System Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
3. Remove the SDM connector, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
4. Test the PPS communication circuit between the SDM and the PPS for a short to ground, a high resistance or an open. Verify short to ground, a high resistance or an open exist. If any of the above conditions are found make the appropriate repair.
5. Replace the PPS.
6. Use the scan tool to clear all PPS DTCs. Rezero the PPS. Refer to «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 036 does not exist. If DTC 036 reset replaced the SDM.

Control Module References for SDM and PPS replacement, setup and programming.

The inflatable restraint passenger presence system (PPS) continuously monitors for critical faults. If the PPS determines there is a fault internal to the electronic control unit (ECU) or sensor mat, the PPS will set DTC 056, turn the passenger air bag status indicator to OFF and notify the sensing and diagnostic module (SDM) of a fault in the PPS through a non class 2 communications circuit. Other DTCs like DTC 034 or DTC 036 may set along with DTC 056. Diagnose all current DTCs before diagnosing DTC 056. The PPS, heated seat element and seat bottom cushion is only service as a complete kit, which is a calibrated system and must be replaced as a complete unit. If a service kit was installed, DTC 056 will be set current and the Rezeroing Procedure must be performed before the DTC can be cleared.

Ignition voltage is between 9-16 volts.

1. PPS ECU internal electronic fault.
2. PPS Sensor mat internal electronic fault.
3. PPS Service kit was installed.

1. The PPS will set a DTC 056 and then communicate with the SDM via non class 2 circuit.
2. The SDM will set DTC B0092.
3. The SDM disables the instrument panel (I/P) module deployment loop.
4. The PPS will turn ON the passenger air bag status OFF indicator.
5. The SDM commands the AIR BAG indicator ON via serial data communications.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

DTC 034 or DTC 036 may set along with DTC 056. Diagnose all current DTCs before diagnosing DTC 056. This DTC 056 indicates that you have installed a service kit or have an internal fault to the ECU or sensor mat.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool. Go to the passenger presence system (PPS) menu, then retrieve the DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 034 or DTC 036 does not set. If either DTC 034 or DTC 036 sets then refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information__diagnostic-trouble-code-dtc-list) .
2. Check to see if the PPS has been replaced. Verify the correct PPS has been installed. If the incorrect PPS was installed replace with the correct PPS. Then perform the «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
3. Perform the «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) and recheck for DTC 0056. Verify that DTC 0056 does not reset. If DTC 0056 sets, then replace the PPS and rezero.

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

The inflatable restraint Passenger Presence System (PPS) continuously monitors for critical faults. If the PPS determines there is a fault internal to the electronic control unit (ECU) or sensor mat, the PPS will set DTC 056, turn the passenger air bag status indicator to OFF and notify the sensing and diagnostic module (SDM) of a fault in the PPS through a non class 2 communications circuit. Other DTCs like DTC 034 or DTC 036 may set along with DTC 056. Diagnose all current DTCs before diagnosing DTC 056. The PPS, heated seat element and seat bottom cushion is only service as a complete kit, which is a calibrated system and must be replaced as a complete unit. If a service kit was installed, DTC 056 will be set current and the Rezeroing Procedure must be performed before the DTC can be cleared.

Ignition voltage is between 9-16 volts.

1. PPS ECU internal electronic fault
2. PPS Sensor mat internal electronic fault
3. PPS Service kit was installed.

1. The PPS will set a DTC 056 and then communicate with the SDM via non class 2 circuit.
2. The SDM will set DTC B0092.
3. The SDM disables the instrument panel (I/P) module deployment loop.
4. The PPS will turn ON the passenger air bag status OFF indicator.
5. The SDM commands the AIR BAG indicator ON via serial data communications.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

DTC 034 or DTC 036 may set along with DTC 056. Diagnose all current DTCs before diagnosing DTC 056. This DTC 056 indicates that you have installed a service kit or have an internal fault to the ECU or sensor mat.

SIR Schematics

See SIR Connector End Views .

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool. Go to the PPS menu, then retrieve the DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify DTC 034 or DTC 036 does not set. If either DTC 034 or DTC 036 sets then refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information__diagnostic-trouble-code-dtc-list) .
2. Check to see if the PPS has been replaced. Verify the correct PPS has been installed. If the incorrect PPS was installed replace with the correct PPS. Then perform the «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
3. Perform the «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) and recheck for DTC 0056. Verify that DTC 0056 does not reset. If DTC 0056 sets, then replace the PPS and rezero.

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

DTC B0012, B0013, B0014, B0016, B0017 or B0018

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the instrument panel (I/P) module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. There are 2 shorting bars used within the I/P module connector which will short together both I/P module stage 1 high and low circuits and both I/P module stage 2 high and low circuits, when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

B0012 stage 2 or B0016 stage 1

The I/P module deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0013 stage 2 or B0017 stage 1

1. The I/P module stage 1 or stage 2 high circuit is less than 2.4 volts and the I/P module stage 1 or stage 2 deployment loop is more than 6 ohms for 500 milliseconds.
2. The I/P module stage 1 or stage 2 deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0014 stage 2 or B0018 stage 1

1. The I/P module stage 1 or stage 2 high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
2. The I/P module stage 1 or stage 2 high circuit is less than 2.4 volts and I/P module stage 1 or stage 2 deployment loop resistance is less than 6 ohms for 500 milliseconds.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR System is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

If there is more than one DTC set diagnose the open DTC first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

Special Tools Required

1. J 38715-A SIR Driver/Passenger Load tool. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
2. J 38715-80 Load Tool Adapter

1. Ignition OFF, disconnect I/P module in-line connector. Refer to «Inflatable Restraint Instrument Panel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for location of connector.
2. Use J 38715-80 to connect the J 38715-A to the harness side of the I/P module in-line wiring harness connector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR and BASE of COLUMN connectors located on the load tool.
3. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0012, B0013, B0014, B0016, B0017 or B0018 is current. If DTC B0012, B0013, B0014, B0016, B0017 or B0018 is history replace the I/P module. Refer to «Inflatable Restraint Instrument Panel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.
4. Ignition OFF, disconnect and remove the J 38715-A and adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Then remove the SDM connector, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) SDM replacement in Repair Instructions.
5. Test the high and low circuits between the SDM and I/P module for a short to voltage, short to ground, an open or low resistance. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
6. If all circuits test normal then replace the SDM.

1. «Inflatable Restraint Instrument Panel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming

DTC B0022, B0024, B0026, B0042, B0043 or B0044

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the steering module module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. There are 2 shorting bars used within the steering wheel module connector which will short together both steering wheel module stage 1 high and low circuits and both steering wheel module stage 2 high and low circuits, when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

B0022 stage 1 or B0042 stage 2

The steering wheel module deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0024 stage 1 or B0043 stage 2

1. The steering wheel module stage 1 or stage 2 high circuit is less than 2.4 volts and the steering wheel module stage 1 or stage 2 deployment loop is more than 6 ohms for 500 milliseconds.
2. The steering wheel module stage 1 or stage 2 deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0026 stage 1 or B0044 stage 2

1. The steering wheel module stage 1 or stage 2 high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
2. The steering wheel module stage 1 or stage 2 high circuit is less than 2.4 volts and steering wheel module stage 1 or stage 2 deployment loop resistance is less than 6 ohms for 500 milliseconds.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR System is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

If there is more than one DTC set diagnose the open DTC first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. J 38715-A SIR Driver/Passenger Load tool. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
2. J 38715-80 SIR Load Tool Adapter (Bottom of Column)
3. J 38715-120 SIR Load Tool Adapter (Top of Column)

1. Ignition OFF, disconnect the steering wheel module. Refer to «Inflatable Restraint Steering Wheel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions. Then use J 38715-120 to connect the J 38715-A to the upper steering wheel coil module in-line wiring harness connectors. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR and STEERING COLUMN connectors located on the load tool.
2. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0022, B0024, B0026, B0042, B0043 or B0044 are set current. If DTC B0022, B0024, B0026, B0042, B0043 or B0044 is history replace the steering wheel module.
3. Ignition OFF, disconnect steering wheel coil module in-line connector. Refer to «Inflatable Restraint Steering Wheel Module Coil Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
4. Use J 38715-80 to connect the J 38715-A to the harness side of the steering wheel coil module in-line wiring harness connector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR and BASE of COLUMN connectors located on the load tool.
5. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0022, B0024, B0026, B0042, B0043 or B0044 are set current. If DTC B0022, B0024, B0026, B0042, B0043 or B0044 is history replace the steering wheel coil module.
6. Ignition OFF, disconnect and remove the J 38715-A and adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Then remove the SDM connector, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
7. Test the high and low circuits between the SDM and steering wheel coil module for a short to voltage, short to ground, an open or low resistance. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
8. If all circuits test normal then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

1. «Inflatable Restraint Steering Wheel Module Coil Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Inflatable Restraint Steering Wheel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
3. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming

DTC B0028, B0029 or B0030

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the roof rail module - right. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. A shorting bar used within the roof rail module - right connector which will short together both roof rail module - right high and low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

B0028

The roof rail module - right deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0029

1. Roof rail module - right high circuit is less than 2.4 volts and the roof rail module - right deployment loop is more than 6 ohms for 500 milliseconds.
2. Roof rail module - right deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0030

1. Roof rail module - right high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
2. Roof rail module - right high circuit is less than 2.4 volts and roof rail module - right deployment loop resistance is less than 6 ohms for 500 milliseconds.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR system is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

If there is more than one DTC set diagnose the open DTC first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. J 38715-A SIR Driver/Passenger Load tool. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
2. J 38715-30A SIR Load Tool Adapter

1. Ignition OFF, remove the right garnish molding and disconnect the roof rail module-right in-line connector. Refer to «Inflatable Restraint Roof Rail Module Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) or «Inflatable Restraint Roof Rail Module Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
2. Use the J 38715-30A adapter to connect the J 38715-A to the harness side of the roof rail module - right in-line connector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR connector located on the load tool.
3. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0028, B0029 or B0030 is set in current. If DTC B0028, B0029 or B0030 is history replace the roof rail module - right.
4. Ignition OFF, disconnect and remove both the J 38715-A and adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Then remove the SDM connector. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
5. Test and repair the high and low circuits between the SDM and roof rail module - right for a short to voltage, short to ground or open/low resistance. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
6. If all circuits test normal then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

1. «Inflatable Restraint Roof Rail Module Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming

DTC B0040, B0041 or B0045

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the roof rail module - left. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. A shorting bar used within the roof rail module - left connector which will short together both roof rail module - left high and low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

B0040

The roof rail module - left deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0041

1. Roof rail module - left high circuit is less than 2.4 volts and the roof rail module - left deployment loop is more than 6 ohms for 500 milliseconds.
2. Roof rail module - left deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0045

1. Roof rail module - left high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
2. Roof rail module - left high circuit is less than 2.4 volts and roof rail module - left deployment loop resistance is less than 6 ohms for 500 milliseconds.

1. The SDM commands the AIR BAG indicator ON via serial data communication.
2. The SIR system is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

If there is more than one DTC set diagnose the open DTC first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. J 38715-A SIR Driver/Passenger Load tool. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
2. J 38715-30A SIR Load Tool Adapter

1. Ignition OFF, remove the left garnish molding and disconnect the roof rail module-left in-line connector. Refer to «Inflatable Restraint Roof Rail Module Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) or «Inflatable Restraint Roof Rail Module Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
2. Use the J 38715-30A to connect the J 38715-A to the harness side of the roof rail module - left in-line connector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR connector located on the load tool.
3. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0040, B0041 or B0045 is set in current. If DTC B0040, B0041 or B0045 is history replace the roof rail module - left.
4. Ignition OFF, disconnect and remove both the J 38715-A and adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Then remove the SDM connector, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
5. Test and repair the high and low circuits between the SDM and roof rail module - left for a short to voltage, short to ground or open/low resistance. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
6. If all circuits test normal then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

1. «Inflatable Restraint Roof Rail Module Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming

The inflatable restraint sensing and diagnostic module (SDM) contains sensing devices that converts vehicle velocity changes to electrical signals. The SDM processes the generated electrical signals and compares them to values stored in memory. When the generated signals exceed the stored values, the SDM performs additional signal processing and compares the generated signals to signals stored in memory. When 2 of the generated signals exceed the stored values, the SDM will cause current to flow through the inflator modules, deploying the inflator modules and causing DTC B0051 to set.

Ignition voltage is between 9-16 volts.

1. The SDM detects a frontal impact of sufficient force to warrant deployment of the frontal modules.
2. The SDM detects a side impact of sufficient force to warrant deployment of a side impact module.

1. The SDM commands the AIR BAG warning lamp ON via serial data communication.
2. The SDM records crash data.

DTC B0051 is a latched code. You cannot clear a latched code. Replace the SDM after following the instructions.

Reference Information

Electrical Information Reference

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition OFF, inspect the vehicle for signs of inflator module or pretensioner deployment. Verify that the vehicle does not show any signs of inflator deployment. If the vehicle displays any signs of inflator deployment go to «Repairs and Inspections Required After a Collision»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. Use a scan tool and observe the SIR DTC display. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information__diagnostic-trouble-code-dtc-list) . The scan tool should indicate DTC B0051 is not set. If DTC B0051 is set then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

Control Module References for SDM replacement, setup and programming.

The inflatable restraint sensing and diagnostic module (SDM) contains sensing devices that converts vehicle velocity changes to electrical signals. The SDM processes the generated electrical signals and compares them to values stored in memory. When the generated signals exceed the stored values, the SDM performs additional signal processing and compares the generated signals to signals stored in memory. When 2 of the generated signals exceed the stored values, the SDM will cause current to flow through the inflator modules, deploying the inflator modules. DTC B0053 will set along with DTC B0051 when a deployment occurs while a circuit malfunction is present in any one of the deployment loops.

Ignition voltage is between 9-16 volts.

1. The SDM detects a frontal impact of sufficient force to warrant deployment of the frontal modules when a current SIR DTC is set.
2. The SDM detects a side impact of sufficient force to warrant deployment of a side impact module when a current SIR DTC is set.

1. The SDM commands the AIR BAG warning lamp ON via serial data communication.
2. The SDM records crash data.

DTC B0053 is a latched code. You cannot clear a latched code. Replace the SDM after following the instructions.

DTC B0053 will be accompanied by another DTC, other than DTC B1000 and DTC B0051. Repair the malfunction causing the other DTCs before installing a new SDM.

Electrical Information Reference

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition OFF, inspect the vehicle for signs of inflator module or pretensioner deployment. Verify that the vehicle does not show any signs of inflator deployment. If the vehicle displays any signs of inflator deployment go to «Repairs and Inspections Required After a Collision»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. Use a scan tool and observe the SIR DTC display. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information__diagnostic-trouble-code-dtc-list) . The scan tool should indicate DTC B0053 is not set. If DTC B0053 is set then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

Control Module References for SDM replacement, setup and programming

DTC B0057, B0058 or B0059

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the seat belt pretensioner - RF. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. A shorting bar used within the seat belt pretensioner - RF connector which will short together both seat belt pretensioner - RF high and low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

B0057

The seat belt pretensioner - RF deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0058

1. Seat belt pretensioner - RF high circuit is less than 2.4 volts and the seat belt pretensioner - RF deployment loop is more than 6 ohms for 500 milliseconds.
2. Seat belt pretensioner - RF deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0059

1. Seat belt pretensioner - RF high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
2. Seat belt pretensioner - RF high circuit is less than 2.4 volts and seat belt pretensioner - RF deployment loop resistance is less than 6 ohms for 500 milliseconds.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR system is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

If there is more than one DTC set diagnose the open DTC first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

J 38715-A SIR Driver/Passenger Load tool. See Special Tools .

1. Ignition OFF, disconnect the seat belt pretensioner - RF wiring harness connector located under the passenger front seat.
2. Use the J 38715-A to connect the harness side of the seat belt pretensioner - RF connector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR connector located on the load tool.
3. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0057, B0058 or B0059 is set current. If DTC B0057, B0058 or B0059 is history replace the seat belt pretensioner - RF.
4. Ignition OFF, disconnect and remove the J 38715-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Then remove the SDM connector. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
5. Test the high and low circuits between the SDM and seat belt pretensioner - RF for a short to voltage, short to ground or open/low resistance. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
6. If all circuits test normal then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

1. «Seat Belt Buckle Pretensioner Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming.

DTC B0064, B0065 or B0066

During a side or frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the seat belt pretensioner - LF. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. A shorting bar used within the seat belt pretensioner - LF connector which will short together both seat belt pretensioner - LF high and low circuits when the connector is disconnected, this will help to prevent unwanted deployment of the inflator module during servicing.

Ignition voltage is between 9-16 volts.

B0064

The seat belt pretensioner - LF deployment loop resistance is less than 1.3 ohms for 500 milliseconds.

B0065

1. Seat belt pretensioner - LF high circuit is less than 2.4 volts and the seat belt pretensioner - LF deployment loop is more than 6 ohms for 500 milliseconds.
2. Seat belt pretensioner - LF deployment loop resistance is more than 4.8 ohms for 500 milliseconds.

B0066

1. Seat belt pretensioner - LF high and/or low circuits is short to ground or short to voltage for 500 milliseconds.
2. Seat belt pretensioner - LF high circuit is less than 2.4 volts and seat belt pretensioner - LF deployment loop resistance is less than 6 ohms for 500 milliseconds.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR system is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

If there is more than one DTC set diagnose the open DTC first.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

J 38715-A SIR Driver/Passenger Load tool. See Special Tools .

1. Ignition OFF, disconnect the seat belt pretensioner - LF wiring harness connector located under the driver front seat.
2. Use the J 38715-A to connect the harness side of the seat belt pretensioner - LF connector. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Use the PASSENGER INFLATOR connector located on the load tool.
3. Ignition ON, use a scan tool to observe the SIR DTC display. Verify DTC B0064, B0065 or B0066 is set current. If DTC B0064, B0065 or B0066 is history replace the seat belt pretensioner - LF.
4. Ignition OFF, disconnect and remove the J 38715-A . See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Then remove the SDM connector. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
5. Test the high and low circuits between the SDM and seat belt pretensioner - LF for a short to voltage, short to ground or open/low resistance. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
6. If all circuits test normal then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

1. «Seat Belt Buckle Pretensioner Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming.

DTC B0077, B0078, B0079, B0080, B0081 or B0082

The inflatable restraint side impact sensor (SIS) utilizes a unidirectional 2-wire circuit. The SIS modulates current on the interface to send ID, state of health (SOH) and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and a ground for the SIS. When the ignition is turned ON and input power from the SDM is first detected, the SIS responds by performing internal diagnostics and sending an ID to the SDM. The SDM considers the ID to be valid if the response time is less than 5 seconds. The SIS continually communicates status messages to the SDM, which determines if a fault is present in the SIS circuit. When a fault is detected, the SDM resets the SIS twice by removing and reapplying power to it. If the fault is still present, the SDM will set a DTC.

Ignition voltage is between 9-16 volts.

All of the following conditions exist for 2.5 seconds

B0077 for SIS - LF or B0078 for SIS - RF

1. A valid ID message is not received within 5 seconds of the SIS being powered up.
2. The SDM has not received a message from the SIS for more than 375 milliseconds.
3. The SDM has reset the SIS twice without detecting a valid ID message.

B0079 for SIS - LF or B0081 for SIS - RF

1. The SDM has received an ID message from the SIS which does not match the ID stored in the SDM memory.
2. The SDM has reset the SIS twice without detecting a correct ID message.

B0080 for SIS - LF or B0082 for SIS - RF

The SDM has received a NOK message from the SIS.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR system is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool as clear SIR codes then recheck for DTCs. Verify that DTC B0079, B0080, B0081 or B0082 is not set. If DTC B0079 or B0080 is set current, replace the SIS left. If DTC B0081 or B0082 is set current, replace the SIS right.
2. If DTC B0077 is current, disconnect the left SIS connector or if DTC B0078 is current, disconnect the right SIS connector. Refer to «Inflatable Restraint Side Impact Sensor Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for location of connector.
3. Remove the SDM connector. Refer to SDM «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
4. Test the signal and voltage circuits between the SDM and SIS. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found, make the appropriate repair.
5. Reconnect all SIR components. Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs. Verify no DTCs are set. If DTC B0077 was current, replace the left SIS. If DTC B0078 was current, replace the right SIS. After replacement, refer to «Repair Verification»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__repair-verification) .

1. «Inflatable Restraint Side Impact Sensor Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming

Repair Verification

Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs. Verify no DTCs are set.

1. If DTC B0077 or B0078 was current, replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. When the SDM has completed the power-up mode, the SDM will establish communication with the Passenger Presence System (PPS). The PPS will respond by commanding both the PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. The SDM will transmit a request message to the PPS to receive the PPS verification ID. The PPS will transmit the verification ID to the SDM and the SDM will compare the ID received to data stored in memory. The SDM will also set DTC B0092 to notify the driver that the PPS has a current malfunction present. When the SDM detects that the PPS has set any one of the following DTCs 032, 034, 036, 052 or 056 the SDM will then disable the instrument panel (I/P) module deployment loop, set DTC B0092 and command the AIR BAG indicator ON.

Ignition voltage is between 9-16 volts.

1. The SDM has detected the PPS has set a DTC.
2. The SDM has loss or no communication with the PPS.

1. The SDM will disable the I/P module deployment loop.
2. The SDM commands the AIR BAG indicator ON via serial data communication.
3. The PPS will turn ON the PASSENGER AIR BAG OFF indicator.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

DTC B0092 is an indication that the SDM has no or loss communication with the PPS or the PPS has internal faults/DTCs. The SDM will communicate to request the verification ID from the PPS for 5 seconds. If the SDM does not receive the verification ID from the PPS within 5 seconds the SDM will set the DTC as current, illuminate the AIR BAG indicator and disable the I/P deployment loop.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, the PPS should turn ON the PPS ON/OFF indicators. Verify the PPS illuminates the PPS ON/OFF indicators. If the Passenger Air Bag ON/OFF status indicator does not illuminate refer to «Passenger Presence System Indicator Circuit Malfunction»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. Ignition ON, use the scan tool. Go to the PPS menu, then retrieve the DTCs. Refer to «Passenger Presence System Flash Code Procedures»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . Verify no PPS DTCs are set. If the PPS has any current or history DTCs stored, you must address the PPS DTCs first. Refer to the «Diagnostic Trouble Code (DTC) List - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information__diagnostic-trouble-code-dtc-list) .
3. Ignition OFF, disconnect the PPS module connector. Note: Refer to «Inflatable Restraint Passenger Presence System Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
4. Remove the SDM connector, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
5. Test the occupant sensor serial data circuit for an open, short to ground or high resistance between the PPS and SDM connector. Verify no open, short to ground or high resistance exists. If any of the above conditions are found make the appropriate repair.
6. Test the PPS ignition 1 voltage and ground circuits for a short to ground, a short to voltage, a high resistance or an open. Verify no short to ground, a short to voltage, a high resistance or an open exists. If any of the above conditions are found make the appropriate repair.
7. If all circuits test normal then replace the PPS.

Control Module References for PPS and SDM replacement, setup and programming.

When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. When the SDM has completed the power-up mode, the SDM will establish communication with the Passenger Presence System (PPS). The PPS will respond by commanding both of the PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. The SDM will then transmit a request message to the PPS to receive the PPS verification ID. The PPS will transmit the verification ID to the SDM and the SDM will compare the ID received to data stored in memory. If the data stored in memory does not match the information transmitted by the PPS, the SDM will set DTC B0098 and command the AIR BAG indicator ON.

Ignition voltage is between 9-16 volts.

The SDM has received an incorrect PPS verification ID.

1. The SDM will disable the instrument panel (I/P) module deployment loop.
2. The SDM commands the AIR BAG indicator ON via serial data communication.
3. The PPS will turn ON the PASSENGER AIR BAG OFF indicator.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

DTC B0098 is an indication that the SDM has received an incorrect PPS verification ID. The SDM will continue to request the verification ID from the PPS for 5 seconds. If the SDM does not receive the correct verification ID from the PPS within 5 seconds, the SDM will set DTC B0098 as current, illuminate the AIR BAG indicator. If either the SDM or PPS were replaced verify that the correct part numbers were used for the vehicle application.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Check to see if the PPS was replaced. Verify the correct PPS was installed. If the wrong PPS was installed, replace with the correct PPS.
2. Check to see if the SDM was replaced. Verify the correct SDM was installed. If the wrong SDM was installed, replace with the correct SDM.
3. Check to see if DTC B1001 is set. Verify DTC B1001 is not set. If the connector for the PPS is damaged, the PPS must be replaced. If DTC B1001 is current go to «DTC B1001»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
4. Replace the PPS. Ignition ON, use the scan tool to clear the DTCs then recheck for DTC B0098. Verify DTC B0098 does not set. If DTC B0098 resets then replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

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

DTC B0100, B0101, B0102, B0103, B0104 or B0105

The inflatable restraint front end sensor utilizes a unidirectional 2-wire circuit. The front end sensor modulates current on the interface to send ID, State of Health and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and a ground for the front end sensor. When the ignition is turned ON and input power from the SDM is first detected, the SIS responds by performing internal diagnostics and sending an ID to the SDM. The SDM considers the ID to be valid if the response time is less than 5 seconds. The front end sensor continually communicates status messages to the SDM, which determines if a fault is present in the front end sensor circuit. When a fault is detected, the SDM resets the front end sensor twice by removing and reapplying power to it. If the fault is still present, the SDM will set a DTC.

Ignition voltage is between 9-16 volts.

All of the following conditions exist for 2.5 seconds

B0100 for Front End Sensor 1 or B0103 for Front End Sensor 2

1. A valid ID message is not received within 5 seconds of the front end sensor being powered up.
2. The SDM has not received a message from the front end sensor for more than 375 milliseconds.
3. The SDM has reset the front end sensor twice without detecting a valid ID message.

B0101 for Front End Sensor 1 or B0104 for Front End Sensor 2

1. The SDM has received an ID message from the front end sensor, which does not match the ID stored in the SDM memory.
2. The SDM has reset the front end sensor twice without detecting a correct ID message.

B0102 for Front End Sensor 1 or B0105 for Front End Sensor 2

The SDM has received a NOK message from the front end sensor.

1. The SDM commands the AIR BAG indicator ON via serial data communications.
2. The SIR System is disabled and no deployments are allowed.

1. The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
2. A history DTC will clear once 255 malfunction-free ignition cycles have occurred.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool as clear SIR codes then recheck for DTCs. Verify that DTC B0101, B0102, B0104 or B0105 is not set. If DTC B0101 or B0102 is set current replace the front end sensor 1/left. If DTC B0104 or B0105 is set current replace the front end sensor 2/right.
2. If DTC B0100 is current, disconnect the front end sensor 1 connector or if DTC B0103 is current disconnect the front end sensor 2 connector. Refer to «Inflatable Restraint Front End Sensor Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for location of connector.
3. Remove the SDM connector, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for connector location.
4. Test the signal and voltage circuits between the SDM and front end sensor. Verify that a short to voltage, short to ground or open/low resistance does not exist. If any of the above conditions are found make the appropriate repair.
5. Reconnect all SIR components. Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs. Verify no DTCs are set. If DTC B0100 was current replace the front end sensor 1. After replacement, refer to «Repair Instructions»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . If DTC B0103 was current replace the front end sensor 2. After replacement, refer to «Repair Verification»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .

1. «Inflatable Restraint Front End Sensor Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for SDM replacement, setup and programming.

Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs. Verify no DTCs are set.

1. If DTC B0100 or B0103 was current replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

The inflatable restraint sensing and diagnostic module (SDM) stores the vehicles restraint ID from the vehicle identification number (VIN) and the last 4 digits of the SDM part number. When the ignition is turned ON, the SDM compares this information to the information stored in the body control module (BCM) over the serial data communication circuit. If there is a mismatch between the information stored in the SDM and BCM, DTC B1001 will set.

Ignition voltage is between 9-16 volts.

1. The last 4 digits of the SDM part number does not match the last 4 digits stored in the BCM.
2. The VIN stored in the BCM does not match that of the vehicle.

1. The SDM commands ON the AIR BAG warning lamp via serial data communications.
2. The SDM disables all deployments.

1. The last 4 digits of the SDM part number match the last 4 digits stored in the BCM.
2. The restraints ID that is stored in the SDM matches the restraints ID that is stored in the BCM.

This DTC is an indication that an incorrect SDM is installed in the vehicle or that the SDM and/or the BCM were replaced without reprogramming the BCM with the new information.

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition ON, use the scan tool to request SIR DTCs. Verify that DTC B1001 is set as current. If DTC B1001 is history, clear codes and recheck.
2. Using the scan tool check the BCM that is programmed with the VIN. Verify that the BCM is programmed with the correct VIN number with the vehicle VIN plate. If the SDM/BCM has the wrong VIN number, refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for programming.
3. Using the scan tool perform the Setup SDM Part Number into BCM procedure. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions for programming.
4. With the ignition ON use the scan tool to clear the DTCs. Verify that DTC B1001 is cleared. If DTC B1001 was current replace the SDM.

Control Module References for SDM or BCM replacement, setup and programming.

The Passenger Presence System (PPS) is a calibrated system that requires rezeroing anytime the seat cushion trim attachments have been removed or the PPS has been replaced. Also, upon initializing the service kit, this DTC will be set and you must perform the rezeroing function in the scan tool. If the passenger seat has been steam cleaned or been wet or its relay humid, rezeroing may have to be performed after the seat has had a chance to dry out. The procedures below are designed to assist in the rezeroing of the PPS. Before you start, read these procedures carefully and completely. For further information regarding the PPS, refer to SIR System Description and Operation .

Passenger Presence System (PPS) Rezeroing Procedure

1. Empty the front outboard passenger seat.
2. Verify that all SIR and PPS components, connectors and connector position assurances (CPAs) are properly connected and mounted.
3. Install a scan tool.
4. Turn ON the ignition, with the engine OFF.
5. Use the scan tool in order to clear the SIR and PPS DTCs.
6. With a scan tool, request the passenger presence system (PPS) rezeroing procedure.
7. Initiate the PPS rezeroing procedure. The PPS will illuminate both PASSENGER AIR BAG ON and OFF indicators located on the center of IPC until the rezeroing procedure has been completed. When the rezeroing procedure has been successfully completed, the PPS will display the current system status on the PASSENGER AIR BAG ON/OFF indicators located in the center of IPC. If the rezeroing procedure was unsuccessful, both PASSENGER AIR BAG ON and OFF indicators will alternate from no illumination to full illumination in 1 second intervals for 5 seconds. The PPS will treat an unsuccessful rezero attempt as a system fault.
8. If the rezeroing procedure was unsuccessful repeat this procedure. Due to the communication status between the SDM and the PPS module, this procedure may have to be repeated until a successful rezero attempt has been achieved.
9. After the PPS has been successfully rezeroed perform the «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

Symptoms - SIR

1. Perform «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information, before using the symptom tables in order to verify that all of the following are true: There are no DTCs set. The inflatable restraint sensing and diagnostic module (SDM) can communicate via the serial data link.
2. Review the SIR system description and operation in order to familiarize yourself with the system functions. Refer to «SIR System Description and Operation»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the SIR system. Refer to «Checking Aftermarket Accessories»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__checking-aftermarket-accessories) in Wiring Systems.
2. 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

1. Refer to «Air Bag Indicator Circuit Malfunction»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in order to diagnose the symptom.
2. Refer to «Passenger Presence System Indicator Circuit Malfunction»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in order to diagnose the symptom.

When the ignition is turned ON, the instrument panel cluster (IPC) flashes the AIR BAG indicator seven times. The inflatable restraint sensing and diagnostic module (SDM) performs diagnostic tests on the SIR system and then commands the IPC to turn the AIR BAG indicator OFF if no SIR malfunction exists. The AIR BAG indicator is controlled by the SDM via serial data communications. If the ignition 1 voltage is outside of the normal operating voltage range 9-16 volts, the SDM will command the IPC to turn the AIR BAG indicator ON with no diagnostic trouble codes (DTCs) present then disables all deployment loops.

SIR Schematics

SIR Connector End Views

1. Ignition ON, use the scan tool to request the SIR data list display. Observe the Battery Voltage Parameter. The battery voltage on the scan tool should read 9-16 volts. If the voltage is less than 9 volts refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) .
2. Using the scan tool go to Body and Accessories, then go onward to Special Functions to Instrument Panel Cluster and then go to Display Test. In the Display Test mode you can turn ON or OFF all the instrument panel indicators when commanded ON. Commanded the IPC indicators ON. The Air Bag indicator should turn ON. If the Air Bag indicator does not turn ON replace the IPC. Note: The AIR BAG warning indicator is not serviceable separately. The IPC must be serviced/replaced as a complete unit.
3. Replace the SDM. Refer to «Inflatable Restraint Sensing and Diagnostic Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) in Repair Instructions.

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

The PASSENGER AIR BAG ON/OFF indicators are used to notify the driver when the Passenger Presence System (PPS) has enabled or disabled the instrument panel (I/P) inflator module. When the ignition is turned ON, the PPS module is supplied with voltage and commands both PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds; then 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 diagnostic trouble code (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.

A history DTC maybe caused by an intermittent short or open in the ignition 1 circuit for the passenger AIR BAG ON/OFF indicator.

SIR Schematics

SIR Connector End Views

1. «Circuit Testing»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__circuit-testing)
2. «Connector Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing)
4. «Wiring Repairs»(/buick/lacrosse/i-2004-2009/remont/body-electrical/#how-to-diagnosis-repair-the-wiring-systems-testing__wiring-repairs)

1. Ignition OFF, disconnect the PPS module connector located under the passenger seat.
2. Disconnect the Passenger AIR BAG ON/OFF Indicator connector.
3. Test the Passenger AIR BAG ON/OFF indicator ignition 1 voltage circuit for a short to ground, a high resistance or an open. Verify that a short to ground, a high resistance or an open does not exist. If any of the above conditions are found make the appropriate repair.
4. Test both ON and OFF indicator control circuits between the Passenger AIR BAG ON/OFF indicator and the PPS for a short to voltage, high resistance or an open. Verify that a short to voltage, a high resistance or an open does not exist. If any of the above conditions are found make the appropriate repair.
5. Reconnect the PPS connector then turn the ignition ON, engine OFF. Then connect a test lamp between the ignition 1 voltage circuit and Passenger Air Bag OFF indicator control circuit on the Passenger AIR BAG ON/OFF indicator connector. With the passenger front seat empty verify the test lamp illuminate. If test lamp does not illuminate replace the PPS. If test lamp illuminate replace the Passenger AIR BAG ON/OFF Indicator.

1. «Indicator Replacement - Inflatable Restraint IP Module»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/buick/lacrosse/i-2004-2009/remont/communication-devices/#computerintegrating-systems__control-module-references) for PPS replacement, setup and programming

SIR Disabling and Enabling Zones

The SIR system has been divided into Disabling and Enabling Zones. When performing service on or near SIR components or SIR wiring, it may be necessary to disable the SIR components in that zone. It may be necessary to disable more than one zone depending on the location of other SIR components and the area being serviced, refer to SIR Zone Identification Views . Refer to the illustration below, to identify the specific zone or zones in which service will be performed. After identifying the zone or zones, proceed to the disabling and enabling procedures for that particular zone or zones.

Scheme 12

SIR Disabling and Enabling Zones

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. Deployment power is available for as much as 1 minute after disconnecting the vehicle power. 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

1. Do not expose inflator modules to temperatures above 65°C (150°F).
2. Verify the correct replacement part number. Do not substitute a component from a different vehicle.
3. 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 ft) or greater

1. Inflatable restraint sensing and diagnostic module (SDM)
2. Inflatable restraint I/P module
3. Inflatable restraint steering wheel module
4. Inflatable restraint steering wheel module coil
5. Inflatable restraint roof side rail modules
6. Inflatable restraint side impact sensors (SIS)
7. Inflatable restraint seat belt pretensioners
8. Inflatable restraint front end sensor

Disabling Procedure

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR Fuse from the underhood fuse center.
7. Remove the radiator upper air baffle and deflector and locate the left and right front end sensor (1,4).
8. Remove the connector position assurance (CPA) (3,6) from both front end sensors connector (2,5).
9. Remove both front end sensor connectors (2,5) from each front end sensor (1,4).

Enabling Procedure

1. Remove the key from the ignition switch.
2. Connect both front end sensor connectors (2,5) to each front end sensor (1,4).
3. Install both CPA's (3,6) into each front end sensor connector (2,5).
4. Install the radiator upper air baffle and deflector.
5. Install the SIR Fuse.
6. Close the underhood fuse center cover.
7. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
8. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) .

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR Fuse from the underhood fuse center.
7. When disabling the roof rail module go to step 8, if the side impact sensor (SIS) needs disabling then go to step 11.
8. Remove the left rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
9. Remove the connector position assurance (CPA) from the left/driver roof rail module connector (2).
10. Disconnect the left roof rail module wiring harness yellow connector (2) from the left roof rail module (3).
11. Remove the left/driver door trim panel. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.
12. Remove enough of the water deflector to access the SIS.
13. Remove the SIS CPA from the left SIS connector (3).
14. Remove the SIS connector (3) from the SIS (1).

1. Remove the key from the ignition switch.
2. When enabling the SIS proceed to step 3, if the roof rail module needs enabling then go to step 7.
3. Install the left SIS connector (3) to the SIS (1).
4. Install the SIS CPA to the SIS connector (3).
5. Replace and secure the water deflector back over the SIS.
6. Install the left/driver door trim panel. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.
7. Connect the left roof rail module wiring harness yellow connector (2) to the left roof rail module (3).
8. Install the CPA to the left roof rail module connector (2).
9. Install the left rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
10. Install the SIR Fuse.
11. Close the underhood fuse center cover.
12. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
13. Perform the SIR Diagnostic System Check if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR fuse from the underhood fuse center.
7. Remove the left/driver sound insulator from the instrument panel (I/P) (2). Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
8. Remove the connector position assurance (CPA) from the steering wheel module coil yellow connector (1).
9. Disconnect the steering wheel module coil yellow connector (1) from the vehicle harness yellow connector (3).

1. Remove the key from the ignition switch.
2. Connect the steering wheel module coil yellow connector (3) to the vehicle harness yellow connector (1).
3. Install the CPA to the steering wheel module coil yellow connector (1).
4. Install the left sound insulator to the I/P (2). Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
5. Install the SIR Fuse.
6. Close the underhood fuse center cover.
7. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
8. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

1. Turn the steering wheel so that the vehicle wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR Fuse from the underhood fuse center.
7. Remove the right/passenger sound insulator from the instrument panel (I/P) (3). Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
8. Remove the connector position assurance (CPA) from the I/P module yellow connector (1).
9. Disconnect the I/P module yellow connector (1) from the vehicle harness yellow connector (2).

1. Remove the key from the ignition switch.
2. Connect the I/P module yellow connector (1) to the vehicle harness yellow connector (2).
3. Install the CPA to the I/P module yellow connector (1).
4. Install the right sound insulator to the I/P (3). Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
5. Install the SIR Fuse.
6. Close the underhood fuse center cover.
7. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
8. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR Fuse from the underhood fuse center.
7. When disabling the roof rail module go to step 8, if the side impact sensor (SIS) needs disabling then go to step 11.
8. Remove the right rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
9. Remove the connector position assurance (CPA) from the right/passenger roof rail module connector (2).
10. Disconnect the right roof rail module wiring harness yellow connector (2) from the right roof rail module (3).
11. Remove the right/passenger door trim panel. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.
12. Remove enough of the water deflector to access the SIS.
13. Remove the SIS CPA from the right SIS connector (3).
14. Remove the SIS connector (3) from the SIS (1).

1. Remove the key from the ignition switch.
2. When enabling the SIS proceed to step 3, if the roof rail module needs enabling then go to step 7.
3. Install the right SIS connector (3) to the SIS (1).
4. Install the SIS CPA to the SIS connector (3).
5. Replace and secure the water deflector back over the SIS.
6. Install the right/passenger door trim panel. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.
7. Connect the right roof rail module wiring harness yellow connector (2) to the right roof rail module (3).
8. Install the CPA to the right roof rail module connector (2).
9. Install the right rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
10. Install the SIR Fuse.
11. Close the underhood fuse center cover.
12. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
13. Perform the SIR Diagnostic System Check if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR Fuse from the underhood fuse center.
7. Remove the connector position assurance (CPA) from the left/driver seat belt pretensioner connector (1) located under the driver seat.
8. Disconnect the left seat belt pretensioner connector from vehicle wiring harness connector (1).

1. Remove the key from the ignition switch.
2. Connect the left seat belt pretensioner connector to the vehicle wiring harness connector (1).
3. Install the CPA to the seat belt pretensioner connector (1).
4. Install the SIR Fuse.
5. Close the underhood fuse center cover.
6. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
7. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

1. Turn the steering wheel so that the vehicle wheels are pointing straight ahead.
2. Turn the ignition switch to the OFF position.
3. Remove the key from the ignition switch.
4. Open the hood and locate the underhood fuse center on right/passenger shock tower.
5. Lift the cover for the underhood fuse center.
6. Locate and remove the SIR Fuse from the underhood fuse center.
7. When disabling the right/passenger seat belt pretensioner perform step 8, if the sensing and diagnostic module (SDM) needs disabling then use entire procedure.
8. Remove the connector position assurance (CPA) from the right/passenger seat belt pretensioner connector (1) located under the passenger seat.
9. Disconnect the seat belt pretensioner - right connector from vehicle wiring harness connector (1).
10. Remove the right rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
11. Remove the CPA from the right/passenger roof rail module connector (2).
12. Disconnect the right roof rail module wiring harness yellow connector (2) from the right roof rail module (3).
13. Remove the right/passenger sound insulator from the instrument panel (I/P) (3). Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
14. Remove the CPA from the I/P module yellow connector (1).
15. Disconnect the I/P module yellow connector (1) from the vehicle harness yellow connector (2).
16. Remove the left/driver sound insulator from the I/P (2). Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
17. Remove the CPA from the steering wheel module coil yellow connector (1).
18. Disconnect the steering wheel module coil yellow connector (1) from the vehicle harness yellow connector (3).
19. Remove the CPA from the left/driver seat belt pretensioner connector (1) located under the driver seat.
20. Disconnect the seat belt pretensioner-left connector from vehicle wiring harness connector (1).
21. Remove the left rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
22. Remove the CPA from the left/driver roof rail module connector (2).
23. Disconnect the left roof rail module wiring harness yellow connector (2) from the left roof rail module (3).

1. Remove the key from the ignition switch.
2. When enabling the right/passenger seat belt pretensioner proceed to step 3, if the SDM needs enabling then use entire procedure.
3. Connect the seat belt pretensioner-right connector to the vehicle wiring harness connector (1).
4. Install the CPA to the seat belt pretensioner connector (1).
5. Connect the right roof rail module wiring harness yellow connector (2) to the right roof rail module (3).
6. Install the CPA to the right roof rail module connector (2).
7. Install the right rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
8. Connect the I/P module yellow connector (1) to the vehicle harness yellow connector (2).
9. Install the CPA to the I/P module yellow connector (1).
10. Install the right sound insulator to the I/P (3). Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
11. Connect the steering wheel module coil yellow connector (3) to the vehicle harness yellow connector (1).
12. Install the CPA to the steering wheel module coil yellow connector (1).
13. Install the left sound insulator to the I/P (2). Refer to «Closeout/Insulator Panel Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
14. Connect the seat belt pretensioner-left connector to the vehicle wiring harness connector (1).
15. Install the CPA to the seat belt pretensioner connector (1).
16. Connect the left roof rail module wiring harness yellow connector (2) to the left roof rail module (3).
17. Install the CPA to the left roof rail module connector (2).
18. Install the left rear panel. Refer to «Trim Panel Replacement - Rear Quarter Upper»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
19. Install the SIR Fuse.
20. Close the underhood fuse center cover.
21. Use caution while reaching in and turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
22. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/buick/lacrosse/i-2004-2009/remont/oem-general-information/#vehicle-dtc-information) in Vehicle DTC Information.

Scheme 13

Inflatable Restraint Front End Sensor Replacement

Removal Procedure

1. Disable the SIR system. Refer to «SIR Disabling and Enabling Zone 2»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) or to «SIR Disabling and Enabling Zone 6»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. Place the window in the raised position to access the sensor.
3. Remove the door trim panel. Refer to «Trim Panel Replacement - Side Front Door»(/buick/lacrosse/i-2004-2009/remont/door-locks-anti-theft-systems/#door-system-mirror-system-window-system) in Doors.
4. Remove enough of the water deflector to access the side impact sensor (1).
5. Loosen the bolts (2) on the inflatable restraint side impact sensor (1).
6. Remove the inflatable restraint side impact sensor (1) out from the door (4).
7. Remove the connector position assurance (CPA) (3) from the side impact sensor connector (4).
8. Disconnect the side impact sensor connector (4).
9. Remove the sensor from the vehicle.

Installation Procedure

1. Remove any dirt, grease or other impurities from the mounting surface.
2. Position the inflatable restraint side impact sensor by the door.
3. Connect the side impact sensor connector (4).
4. Install the CPA (3) to the side impact sensor connector.
5. Install the side impact sensor (1) to the door (4).
6. Tightening the side impact sensor bolts (2). Tighten: Tighten the bolts to 10 N.m (89 lb in).
7. Install the water deflector to the door.
8. Enable the SIR system. Refer to «SIR Disabling and Enabling Zone 2»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) or to «SIR Disabling and Enabling Zone 6»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .

1. Disable the SIR system. Refer to «SIR Disabling and Enabling Zone 9»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. Remove the passenger front seat. Refer to «Seat Replacement - Front Bucket»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system) in Seats.
3. Remove the right side, center pillar, lower trim panel. Refer to «Trim Panel Replacement - Lower Center Pillar»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
4. Remove the right insulator panel. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
5. Reposition the front and rear door weatherstrips as required.
6. Lift up the carpet to access the inflatable restraint sensing and diagnostic module (SDM).
7. Remove the connector position assurance (CPA) from the connector to the SDM.
8. Disconnect the connector from the SDM.
9. Remove the SDM mounting fasteners (1).
10. Remove the SDM (2) from the floor pan (3).

1. Remove any dirt, grease or other impurities from the mounting surface.
2. Install the SDM (2) horizontally to the vehicle (3).
3. Point the arrow on the SDM toward the front of the vehicle.
4. Install the SDM mounting fasteners (1). Tighten: Tighten the fasteners to 10 N.m (89 lb in).
5. Connect the connector to the SDM.
6. Install the CPA to the SDM connector.
7. Position the carpet to cover the SDM.
8. Reposition the front and rear door weatherstrips as required.
9. Install the center pillar, lower trim panel. Refer to «Trim Panel Replacement - Lower Center Pillar»(/buick/lacrosse/i-2004-2009/remont/exteriorinterior-trim/#interior-trim) in Interior Trim.
10. Install the right insulator panel. Refer to «Closeout/Insulator Panel Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/gauges-instrument-panels/#instrument-panel-gages-and-console) in Instrument Panel, Gages and Console.
11. Install the passenger front seat. Refer to «Seat Replacement - Front Bucket»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system) in Seats.
12. Enable the SIR system. Refer to «SIR Disabling and Enabling Zone 9»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
13. If you replaced the SDM, perform the following procedure in order to update the BCM with the new SDM part number: IMPORTANT: The AIR BAG indicator may remain ON after the SDM is replaced. After programming the SDM part number into the BCM, cycle the ignition switch OFF and ON. This turns OFF the AIR BAG indicator and clears the DTC. Install a scan tool. Select the Special Functions option from the BCM Menu and press enter. Select the BCM Reprogramming in BCM option and press enter. Follow the procedure on the scan tool display. Cycle the ignition switch OFF and ON.

Scheme 14

Inflatable Restraint Steering Wheel Module Replacement

Scheme 15

Inflatable Restraint Steering Wheel Module Coil Replacement

Scheme 16

Inflatable Restraint Instrument Panel Module Replacement

1. Disable the SIR system. Refer to «SIR Disabling and Enabling Zone 9»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. Remove the seat cushion trim cover. Refer to «Seat Cushion Cover Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system) in Seats.
3. Remove the connector position assurance (CPA) and disconnect the electrical connectors from the electronic control unit (ECU) module.
4. Lift the seat cushion pad to access the ECU retaining bolts (3).
5. Remove the bolts that retain the ECU (2) to the seat frame.
6. If replacing the passenger presence system (PPS) with a service kit, it is necessary to remove the three screws holding the ECU to the bracket. The bracket will be unused.
7. Remove the sensor assembly wiring harness attachments from the seat cushion frame. Note the location of the wire routing.
8. Remove the passenger presence system from the seat.

Installation Procedures

1. Position the passenger presence system to the seat making sure to route the wiring correctly.
2. Insert the wiring harness attachment clips into the cushion frame.
3. Install the three ECU retaining bolts that secure the ECU to the bracket. Tighten: Tighten the bolts to 2 N.m (18 lb in).
4. Install the ECU bracket retaining bolts (3) that secure the unit to the seat cushion frame. Tighten: Tighten the bolts to 10 N.m (89 lb in).
5. Connect the electrical connectors to the ECU module and install the CPA.
6. Install the seat cushion trim cover. Refer to «Seat Cushion Cover Replacement - Front»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system) in Seats.
7. Enable the SIR system. Refer to «SIR Disabling and Enabling Zone 9»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
8. Re-zero the passenger presence system. Refer to «Passenger Presence System Rezeroing Procedure»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .

Scheme 17

Indicator Replacement - Inflatable Restraint IP Module

Scheme 18

Inflatable Restraint Roof Rail Module Replacement - Left

Scheme 19

Inflatable Restraint Roof Rail Module Replacement - Right

1. Disable the SIR system. Refer to «SIR Disabling and Enabling Zone 7»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) or to «SIR Disabling and Enabling Zone 9»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
2. For pretensioner handling and scrapping refer to «Pretensioner Handling and Scrapping»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
3. Remove the seat bolts. Refer to «Seat Replacement - Front Bucket»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system) in Seats.
4. Tip the seat forward, remove the position assurance pin (2) and disconnect the pretensioner electric connector (1) from the body harness.
5. Disconnect the seat harness connector from the body harness.
6. Disconnect the pretensioner electrical connector from the seat electrical harness.
7. If equipped, disconnect the seat belt reminder cable.
8. Remove the nut from the seat belt pretensioner.
9. Remove the wiring harness from the seat belt pretensioner through the seat bottom frame.
10. Remove the pretensioner from the seat.

1. Position the pretensioner to the seat bottom frame.
2. Position the wiring harness to the seat belt pretensioner through the seat bottom frame.
3. Connect the pretensioner electrical connector to the seat electrical harness.
4. If equipped, connect the seat belt reminder cable.
5. Install the nut to the seat belt pretensioner. Tighten: Tighten the nut to 35 N.m (26 lb ft).
6. Install the pretensioner electric connector (1) and position assurance pin (2) to the body harness.
7. Connect the seat harness connector to the body harness.
8. Install the driver seat bolts. Refer to «Seat Replacement - Front Bucket»(/buick/lacrosse/i-2004-2009/remont/seats/#seat-system) in Seats.
9. Enable the SIR system. Refer to «SIR Disabling and Enabling Zone 7»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) or to «SIR Disabling and Enabling Zone 9»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
10. If the pretensioner is to be scrapped, deploy the pretentioner. Refer to «Pretensioner Handling and Scrapping»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
11. If the pretentioner is to be returned undeployed to the manufacturer for warranty, refer to «Pretensioner Handling and Scrapping»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .

Accident With or Without Air Bag Deployment - Component Inspections

After a collision, inspect the following components as indicated. If any damage is detected, replace the component. If damage to the mounting points or mounting hardware is detected, repair the component or replace the hardware as needed.

1. Steering column-Perform the steering column accident damage checking procedures. Refer to «Steering Column Accident Damage Inspection»(/buick/lacrosse/i-2004-2009/remont/ignition-switchsteering-lock/#steering-wheel-steering-column__steering-column-accident-damage-inspection) in Steering Wheel and Column.
2. Instrument panel (I/P) knee bolsters and mounting points-Inspect the knee bolsters for bending, twisting, buckling or any other type of damage.
3. I/P brackets, braces, etc.-Inspect for bending, twisting, buckling or any other type of damage.
4. Seat belts-Perform the seat belt operational and functional checks. Refer to «Operational and Functional Checks»(/buick/lacrosse/i-2004-2009/remont/restraints-control-systems/#seat-belt-system__operational-and-functional-checks) in Seat Belts.
5. Seats and seat mounting points-Inspect for bending, twisting, buckling or any other type of damage.
6. Passenger seat bottom with passenger presence system (PPS)-Check for any DTCS or problems that may cause the PPS not to function properly.
7. The roof and headliner mounting points.

Frontal Inflator Module Deployment

After a collision involving air bag deployment, replace the following components.

1. Inflatable restraint I/P module, if deployed and after performing the necessary inspections listed above
2. Inflatable restraint steering wheel module
3. Inflatable restraint SDM
4. Inflatable restraint front end sensor, left/right
5. Inflatable restraint seat belt pretensioners

Perform additional inspections on the following components.

1. Steering wheel module coil and the coil wiring pigtail-Inspect for melting, scorching or other damage due to excessive heat.
2. Mounting points or mounting hardware for the I/P, steering wheel module, SDM and pretensioners-Inspect for any damage and repair or replace each component as needed.

Accident With Side Air Bag Deployment - Component Replacement and Inspections

After a collision involving side air bag deployment, replace the following components.

1. Inflatable restraint side impact sensors (SIS), left/right, on the side of the impact
2. Inflatable restraint roof rail module, left/right, on the side of the impact
3. Inflatable restraint SDM
4. Inflatable restraint seat belt pretensioner

Perform additional inspections on the following components.

1. Mounting points or mounting hardware for the SIS-Inspect for any damage and repair or replace each component as needed.
2. Mounting points or mounting hardware for the roof rail module (left/right) on the side of impact-Inspect for any damage and repair or replace each component as needed.
3. Mounting points or mounting hardware for the SDM and seat belt pretensioners-Inspect for any damage and repair or replace each component as needed.

Tools Required

1. J 38826 SIR Deployment Harness. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
2. J 39401-B SIR Deployment Fixture. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
3. J 38826-25 Roof rail module adapter
4. J 38826-75 Steering wheel module adapter (dual stage air bags)
5. J 38826-80 I/P module adapter (dual stage air bags)

Live (Undeployed) Inflator Module

Scheme 20

Use caution when handling or storing a live (undeployed) inflator module. An inflator module deployment produces a rapid generation of gas. This may cause the inflator module or an object in front of the inflator module, to project through the air in the event of an unlikely deployment.

Dual Stage Inflator Module

Dual stage inflator modules have two deployment stages. If stage 1 was used to deploy a dual stage inflator module, stage 2 may still be active. Therefore, a deployed dual stage inflator module must be treated as an active module. If disposal of a deployed or undeployed dual stage module is required both deployment loops must be energized to deploy the air bag.

Scrapping Procedure

During the course of a vehicle's useful life, you may need to dispose of a live (undeployed) inflator module. Do not dispose of a live (undeployed) inflator module through normal disposal channels until the inflator module has been deployed. The following information covers the proper procedures for the disposing of a live (undeployed) inflator module.

Do not deploy the inflator module in the following situations

1. After replacement of an inflator module under warranty. The inflator module may need to be returned undeployed to the manufacturer.
2. If the vehicle is the subject of a Product Liability report related to the SIR system and is subject to a Preliminary Investigation (GM-1241). Do not alter the SIR system in any manner.
3. If the vehicle is involved in a campaign affecting the inflator modules. Follow the instructions in the campaign service bulletin for proper SIR handling procedures.

Deployment Procedures

The inflator module can be deployed inside or outside of the vehicle. The method used depends upon the final disposition of the vehicle. Review the following procedures in order to determine which will work best in a given situation

Deployment Outside Vehicle (Steering Wheel Module, I/P Module and Roof Rail Module)

Deploy the inflator module outside of the vehicle when the vehicle will be returned to service, for seat belt pretensioner deployment outside the vehicle refer to Pretensioner Handling and Scrapping . Situations that require deployment outside of the vehicle include the following

1. Using the SIR diagnostics, determine that the inflator module is malfunctioning.
2. The inflator module is cosmetically damaged, scratched or ripped.
3. The inflator module pigtail (if equipped) is damaged.
4. The inflator module connector is damaged.
5. The inflator module connector terminals are damaged.

Deployment and disposal of a malfunctioning inflator module is subject to any required retention period.

1. Turn OFF the ignition.
2. Remove the ignition key.
3. Put on safety glasses.
4. Remove the inflator module. Refer to the following: If you are removing the steering wheel module, refer to «Inflatable Restraint Steering Wheel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . If you are removing the I/P module, refer to «Inflatable Restraint Instrument Panel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) . If you are removing a roof rail module, refer to «Inflatable Restraint Roof Rail Module Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) and/or «Inflatable Restraint Roof Rail Module Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
5. Place the inflator module with the vinyl trim cover facing up and away from the surface on a work bench.
6. Clear a space on the ground about 1.85 m (6 ft) in diameter for deployment of the inflator module. If possible, use a paved, outdoor location free of activity. Otherwise, use a space free of activity on the shop floor. Make sure you have sufficient ventilation.
7. Make sure no loose or flammable objects are in the area.
8. When deploying the steering wheel module, place the steering wheel module in the center of the space.
9. When deploying the I/P module, refer to the following instructions: Place J 39401-B (2) in the center of the cleared area. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Fill the deployment fixture with water or sand. Using the proper nuts and bolts, mount the I/P module (1) to the deployment fixture (2), with the vinyl trim facing up. Securely tighten all fasteners that hold the I/P module (1) to the deployment fixture (2) prior to deployment.
10. If you have a roof rail module, refer to the following instructions: Place the SIR deployment fixture (3) in the center of the cleared area. Fill the deployment fixture with water or sand. Using the proper nuts (2) and mount the roof rail module (1) to the deployment fixture (3), with the vinyl face up. Adjust and secure the fixture arms (4) to the deployment fixture (3). Securely tighten all fasteners that hold the side impact module (1) to the deployment fixture (3) prior to deployment.
11. Inspect J 38826 and the appropriate pigtail adapter for damage. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Replace as needed.
12. Short the two SIR deployment harness (1) leads together using one banana plug seated into the other.
13. Connect the appropriate pigtail adapter (2) to the SIR deployment harness (1).
14. Extend the SIR deployment harness and adapter to full length from the deployment fixture.
15. Connect the inflator module (1) to the adapter (2) on the SIR deployment harness (3).
16. Clear the area of people.
17. Place a 12 V minimum/2 A minimum power source, such as a vehicle battery, near the shorted end of the SIR deployment harness.
18. Separate the 2 banana plugs on the SIR deployment harness.
19. Connect the SIR deployment harness wires to the power source. Inflator module deployment will occur when contact is made.
20. Disconnect the SIR deployment harness from the power source.
21. Seat one banana plug into the other in order to short the deployment harness leads.
22. If the inflator module did not deploy, disconnect the adapter and discontinue the procedure. Contact the Technical Assistance Group. Otherwise, proceed to the following steps.
23. Put on a pair of shop gloves.
24. Disconnect the pigtail adapter from the inflator module as soon as possible.
25. Dispose of the deployed inflator module through normal refuse channels.
26. Wash hands with a mild soap.

Deployment Inside Vehicle (Vehicle Scrapping Procedure)

Deploy the inflator modules inside of the vehicle when destroying the vehicle or when salvaging the vehicle for parts. This includes, but is not limited to, the following situations

1. The vehicle has completed a useful life.
2. Irreparable damage occurs to the vehicle in a non-deployment type accident.
3. Irreparable damage occurs to the vehicle during a theft.
4. The vehicle is being salvaged for parts to be used on a vehicle with a different VIN as opposed to rebuilding as the same VIN.

1. Turn OFF the ignition.
2. Remove the ignition key.
3. Put on safety glasses.
4. Remove all loose objects from the front seats.
5. Disable the SIR system. Refer to «SIR Disabling and Enabling Zones»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__sir-disabling-and-enabling-zones) .
6. Disconnect the steering wheel module yellow connector (1) from vehicle harness yellow connector (3).
7. Cut the yellow harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
8. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
9. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gage) or thicker multi-strand wire. Use these wires to fabricate the driver deployment harness.
10. Strip 13 mm (0.5 in) of insulation from both ends of the wires cut in the previous step.
11. Twist together one end from each of the wires in order to short the wires. Deployment wires shall remain shorted and not connected to a power source until you are ready to deploy the inflator module.
12. Twist together two connector wire leads (the high circuits from both stages of the steering wheel module) to one sets of deployment wires. Refer to «SIR Connector End Views»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__sir-connector-end-views) in order to determine the correct circuits.
13. Inspect that the 3 wire connection is secure.
14. Bend flat the twisted connection.
15. Secure and insulate the 3 wire connection to deployment harness using electrical tape.
16. Twist together two connector wire leads (the low circuits from both stages of the steering wheel module) to one sets of deployment wires. Refer to «SIR Connector End Views»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__sir-connector-end-views) in order to determine the correct circuits.
17. Inspect that the 3 wire connection is secure.
18. Bend flat the twisted connection.
19. Secure and insulate the 3 wire connection to deployment harness using electrical tape.
20. Connect the deployment harness to the steering wheel module in-line connector.
21. Route the deployment harness out of the driver side of the vehicle.
22. Disconnect the driver/left seat belt pretensioner yellow connector (1) from the vehicle wiring harness located under the rear of driver seat.
23. Cut the harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
24. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
25. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gage) or thicker multi-strand wire. These wires will be used to fabricate the left seat belt pretensioner deployment harness.
26. Strip 13 mm (0.5 in) of insulation from both ends of the wires cut in the previous step.
27. Twist together one end from each of the wires in order to short the wires.
28. Twist together one connector wire lead to one deployment wire.
29. Bend flat the twisted connection.
30. Secure and insulate the connection using electrical tape.
31. Twist together, bend and tape the remaining connector wire lead to the remaining deployment wire.
32. Connect the deployment harness to the left seat belt pretensioner yellow connector.
33. Route the deployment harness out of the driver side of the vehicle.
34. Disconnect the left/driver roof rail module yellow harness connector (2).
35. Cut the harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
36. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
37. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gage) or thicker multi-strand wire. These wires will be used to fabricate the roof rail module deployment harness.
38. Strip 13 mm (0.5 in) of insulation from both ends of the wires cut in the previous step.
39. Twist together one end from each of the wires in order to short the wires.
40. Twist together one connector wire lead to one deployment wire.
41. Bend flat the twisted connection.
42. Secure and insulate the connection using electrical tape.
43. Twist together, bend and tape the remaining connector wire lead to the remaining deployment wire.
44. Connect the deployment harness to the roof rail module.
45. Route the deployment harness out of the driver side of the vehicle.
46. Disconnect the I/P module yellow harness connector (1) from the vehicle harness connector (2).
47. Cut the yellow harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
48. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
49. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gage) or thicker multi-strand wire. These wires will be used to fabricate the IP module deployment harness.
50. Strip 13 mm (0.5 in) of insulation from both ends of the wires cut in the previous step.
51. Twist together one end from each of the wires in order to short the wires.
52. Twist together two connector wire leads (the high circuits from both stages of the steering wheel module) to one sets of deployment wires. Refer to «SIR Connector End Views»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__sir-connector-end-views) in order to determine the correct circuits.
53. Inspect that the 3 wire connection is secure.
54. Bend flat the twisted connection.
55. Secure and insulate the 3 wire connection to deployment harness using electrical tape.
56. Twist together 2 connector wire leads (the low circuits from both stages of the steering wheel module) to one sets of deployment wires. Refer to «SIR Connector End Views»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__sir-connector-end-views) in order to determine the correct circuits.
57. Inspect that the 3 wire connection is secure.
58. Bend flat the twisted connection.
59. Secure and insulate the 3 wire connection to deployment harness using electrical tape.
60. Connect the deployment harness to the I/P module in-line connector.
61. Route the deployment harness out of the passenger side of the vehicle.
62. Disconnect the passenger/right seat belt pretensioner yellow connector (1) from the vehicle wiring harness located under the rear of passenger seat.
63. Cut the harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
64. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
65. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gage) or thicker multi-strand wire. These wires will be used to fabricate the right seat belt pretensioner deployment harness.
66. Strip 13 mm (0.5 in) of insulation from both ends of the wires cut in the previous step.
67. Twist together one end from each of the wires in order to short the wires.
68. Twist together one connector wire lead to one deployment wire.
69. Bend flat the twisted connection.
70. Secure and insulate the connection using electrical tape.
71. Twist together, bend and tape the remaining connector wire lead to the remaining deployment wire.
72. Connect the deployment harness to the right seat belt pretensioner yellow connector.
73. Route the deployment harness out of the passenger side of the vehicle.
74. Disconnect the right/passenger roof rail module yellow harness connector (2).
75. Cut the harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
76. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
77. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gage) or thicker multi-strand wire. These wires will be used to fabricate the roof rail module deployment harness.
78. Strip 13 mm (0.5 in) of insulation from both ends of the wires cut in the previous step.
79. Twist together one end from each of the wires in order to short the wires.
80. Twist together one connector wire lead to one deployment wire.
81. Bend flat the twisted connection.
82. Secure and insulate the connection using electrical tape.
83. Twist together, bend and tape the remaining connector wire lead to the remaining deployment wire.
84. Connect the deployment harness to the roof rail module.
85. Route the deployment harness out of the passenger side of the vehicle.
86. Completely cover the windshield and front door window openings with a drop cloth.
87. Stretch out all of the deployment harness wires on the right side of the vehicle to their full length.
88. Deploy each deployment loop one at a time.
89. Place a power source, 12 V minimum/2 A minimum (i.e., a vehicle battery) near the shorted end of the harnesses.
90. Separate the one set of wires and touch the wires ends to the power source in order to deploy the inflator modules, doing one module at a time.
91. Disconnect the deployment harness from the power source and twist the wire ends together.
92. Continue the same process with the remaining deployment harnesses that are available.
93. Stretch out all of the deployment harness wires on the left side of the vehicle to their full length.
94. Deploy each deployment loop one at a time.
95. Place a power source, 12 V minimum/2 A minimum (i.e., a vehicle battery) near the shorted end of the harnesses.
96. Separate the one set of wires and touch the wires ends to the power source in order to deploy the inflator modules, doing one module at a time.
97. Disconnect the deployment harness from the power source and twist the wire ends together.
98. Continue the same process with the remaining deployment harnesses that are available.
99. Remove the drop cloth from the vehicle.
100. Disconnect all harnesses from the vehicle.
101. Discard the harnesses.
102. Scrap the vehicle in the same manner as a non-SIR equipped vehicle.
103. If one or all of the inflator modules did not deploy, perform the following steps to remove the undeployed module(s) from the vehicle: «Inflatable Restraint Steering Wheel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) «Inflatable Restraint Instrument Panel Module Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) «Inflatable Restraint Roof Rail Module Replacement - Left»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) «Inflatable Restraint Roof Rail Module Replacement - Right»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) «Seat Belt Buckle Pretensioner Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system)

Scheme 21

1. J 38826 SIR Deployment Harness. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
2. J 38826 -25 for seat belt pretensioner module adapter. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
3. J 39401-B SIR Deployment Fixture. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .

During the course of a vehicle's useful life, certain situations may arise which will necessitate the disposal of a live (undeployed) pretensioner. The following information covers the proper procedures for the disposing of a live (undeployed) pretensioner. Deploy the pretensioner before disposal. Do not dispose of a live (undeployed) pretensioner through normal disposal channels until the pretensioner has been deployed. The following information covers the proper procedures for the disposing of a live (undeployed) pretensioner.

1. After replacement of a pretensioner under warranty. The pretensioner may need to be returned undeployed to the original manufacturer of pretensioner.
2. If the vehicle is the subject of a Product Liability report related to the SIR system and is subject to a Preliminary Investigation (GM-1241). Do not alter the SIR system in any manner.
3. If the vehicle is involved in a campaign affecting the pretensioners. Follow the instructions in the Campaign Service Bulletin for proper SIR handling procedures.

The pretensioner can be deployed inside or outside of the vehicle. The method used depends upon the final disposition of the vehicle. Review the following procedures in order to determine which will work best in a given situation.

Deployment Inside the Vehicle

Refer to Inflator Module Handling and Scrapping for deploying the pretensioner inside vehicle under Vehicle Scrapping Procedure.

Deployment Outside Vehicle for Seat Belt Pretensioners

Deploy the seat belt pretensioners outside of the vehicle when the vehicle will be returned to service. Situations that require deployment outside of the vehicle include the following

1. Using the SIR diagnostics, you determine that the seat belt pretensioner is malfunctioning.
2. The pretensioner pigtail is damaged.
3. The pretensioner connector is damaged.
4. The pretensioner connector terminal is damaged.

Deployment and disposal of a malfunctioning seat belt pretensioner is subject to any required retention period.

1. Turn the ignition switch to the OFF position.
2. Remove the ignition key.
3. Put on safety glasses.
4. Remove the seat belt pretensioner from the vehicle. Refer to «Seat Belt Buckle Pretensioner Replacement»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system) .
5. When carrying a pretensioner to the deployment area keep the open end of pretensioner pointed away from the body.
6. Clear a space on the ground about 1.85 M (6 ft) in diameter for deployment of the pretensioner. If possible, use a paved, outdoor location free of activity. Otherwise, use a space free of activity on the shop floor. Make sure you have sufficient ventilation.
7. Make sure no loose or flammable objects are in the area.
8. Place J 39401-B in the center of the cleared area. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) .
9. Fill the fixture plastic reservoir with water or sand.
10. Mount the module (1) in the SIR deployment fixture (3) with the open end facing up using the following mounting method. Adjust and secure the arms (4) of J 39401-B to the deployment fixture (3). See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . To mount, use the proper size bolt (2) and nut (5) with washers in order to secure the pretensioner (1) to the deployment fixture brackets (4). Securely tighten all fasteners prior to deployment.
11. Inspect the J 38826 SIR Deployment Harness and the appropriate pigtail adapter for damage. See «Special Tools»(/buick/lacrosse/i-2004-2009/remont/airbag/#supplemental-inflatable-restraint-system__special-tools) . Replace as needed.
12. Short the 2 SIR deployment harness (1) leads together using one banana plug seated into the other.
13. Connect the appropriate pigtail adapter (2) to the SIR deployment harness (1).
14. Extend the SIR deployment harness and adapter to full length from the deployment fixture.
15. Connect the pretensioner (1) to the adapter (2) on the deployment harness (3).
16. Clear the area of people.
17. Separate the 2 banana plugs on the SIR deployment harness.
18. Place a 12 V minimum/2 A minimum power source, such as a vehicle battery, near the shorted end of the harness.
19. Connect the SIR deployment harness wires to the power source. Pretensioner deployment will occur when contact is made.
20. Disconnect the SIR deployment harness from the power source after the pretensioner deploys.
21. Seat 1 banana plug into the other in order to short the deployment harness leads.
22. If the pretensioner did not deploy, disconnect the adapter and discontinue the procedure. Contact the Technical Assistance Group. Otherwise, proceed to the following steps.
23. Put on a pair of shop gloves.
24. Disconnect the pigtail adapter from the pretensioner as soon as possible.
25. Inspect the pigtail adapter and the SIR deployment harness. Replace as needed.
26. Dispose of the deployed pretensioner through normal refuse channels.
27. Wash your hands with a mild soap.

Scheme 22

The supplemental inflatable restraint (SIR) system supplements the protection offered by the occupants seat belt system (2). The SIR system may contain several inflator modules located throughout the vehicle, i.e. steering wheel module (1), instrument panel (I/P) module (1) or side impact modules. In addition to inflator modules, the vehicle may contain seat belt pretensioners that tighten the seat belt in the event of a collision, thus reducing the distance between the occupant and the seat belt when an inflator module is deployed. Each inflator module has a deployment loop that is controlled by the sensing and diagnostic module (SDM) mounted inside the vehicle. The SDM determines the severity of a collision with the assistance of various sensor inputs located at strategic points on the vehicle. When the SDM detects a collision of sufficient force it will process the information provided by the sensors to further support air bag deployment. The SDM performs continuous diagnostic monitoring of the SIR system electrical components. Upon detection of a circuit malfunction, the SDM will set a DTC and inform the driver by turning the AIR BAG indicator ON. The steering column (1) and knee bolsters (3) are designed to absorb energy and compress during frontal collisions in order to limit leg movement and decrease the chance of injury to the driver and passenger. After an air bag deployment, the SDM will send out a post-air message to the body control module (BCM). The BCM will unlock the doors and turn ON the interior lights 15 seconds after receipt of this message.

Frontal SIR System Description

The frontal SIR system consists of the following components

1. AIR BAG indicator located in the instrument panel cluster (IPC)
2. Driver and passenger knee bolsters
3. Inflatable restraint front end sensor (left/right)
4. Inflatable restraint instrument panel (I/P) module
5. Inflatable restraint sensing and diagnostic module (SDM)
6. Inflatable restraint steering wheel module
7. Inflatable restraint steering wheel module coil
8. Inflatable restraint Passenger AIR BAG ON/OFF indicator
9. Inflatable restraint passenger presence system (PPS)
10. Inflatable restraint seat belt pretensioners
11. Inflatable restraint wiring harnesses
12. Steering wheel and column

A frontal collision of sufficient force up to 30 degrees off the longitudinal centerline of the vehicle will deploy the frontal air bags. The SDM contains a sensing device that converts vehicle velocity changes to an electrical signal. In the event of a frontal collision, the SDM receives a signal from the electronic frontal sensor, which assists the SDM in determining the severity of the collision. The SDM compares these signals to a value stored in memory. When the generated signals exceed the stored value, the SDM will cause current to flow through the frontal deployment loops simultaneously deploying the frontal air bags. The SDM, I/P, steering wheel module, steering wheel module coil and the connecting wires makeup the frontal deployment loops. The SDM continuously monitors the deployment loops for malfunctions and turns the AIR BAG indicator ON if a fault is detected.

Inflatable Restraint Sensing and Diagnostic Module (SDM)

The sensing and diagnostic module (SDM) is a microprocessor and the control center for the SIR system. The SDM contains internal sensors along with several external sensors, if equipped, mounted at strategic locations on the vehicle. In the event of a collision, the SDM compares the signals from the internal and external sensors to a value stored in memory. When the generated signals exceed the stored value, the SDM will cause current to flow through the appropriate deployment loops to deploy the air bags. The SDM records the SIR system status when a deployment occurs and turns the AIR BAG indicator located in the instrument panel cluster (IPC) ON. The SDM performs continuous diagnostic monitoring of the SIR system electrical components and circuitry when the ignition is turned ON. If the SDM detects a malfunction, a DTC will be stored and the SDM will command the AIR BAG indicator ON, notifying the driver that a malfunction exist. In the event that ignition positive voltage is lost during a collision, the SDM maintains a 23-volt loop reserve (23 VLR) for deployment of the air bags. It is important when disabling the SIR system for servicing or rescue operations to allow the 23 VLR to dissipate, which could take up to 1 minute.

Inflatable Restraint Passenger Presence System

The PPS is used to monitor the weight of an occupant on the front outboard passenger seat and communicate the status to the sensing and diagnostic module (SDM) whether to enable or suppress the deployment of the instrument panel (I/P) inflator module. The PPS consist of an electronic control module, sensor mat, heated seat element (if equipped), wiring harness and PASSENGER AIR BAG ON/OFF indicators. The sensor is made up of several flexible conductive metal strips placed underneath the seat cushion trim. These sensor strips transmit and receive a low-level electric field. The weight of the occupant sitting in the front passenger seat is measured as a change in current flow within the sensor mat. If the sensor determines that the occupant weight is less than a specified value, the PPS module will send a suppress signal to the SDM to disable the I/P module. If the sensor determines the occupant weight is higher than a specified value, the PPS module will send an enable signal to the SDM to enable the I/P. The PPS module will notify the customer of the enable/disable status by turning on one of the PASSENGER AIR BAG ON/OFF indicators located in the center of the instrument panel cluster (IPC). The PPS monitors itself for faults and will display flash diagnostic trouble codes (DTCs) when a fault is detected and the SDM commands it by using the PASSENGER AIR BAG ON/OFF indicators. The PPS will also notify the SDM of a fault and the SDM will request the IPC to turn the AIR BAG indicator located on the IPC ON. To determine what DTCs have been set by the PPS, the scan tool is used to command the SDM to request the PPS to flash the DTCs using the PASSENGER AIR BAG ON/OFF indicators located on the I/P.

Inflatable Restraint PASSENGER AIR BAG ON/OFF indicator

The PASSENGER AIR BAG ON/OFF indicators located in the center of the instrument panel cluster (IPC), is used to notify the driver and passenger when the I/P air bag is enable or disable. The PASSENGER AIR BAG ON/OFF indicators are also used to display any faults/DTCs, when the sensing and diagnostic module (SDM) sends a command to the passenger presence system (PPS), the PPS will flash the ON/OFF indicators. The PPS will flash the first number of the DTC using the OFF indicator. This will be an ODD number, then flash the second number of the DTC using the ON indicator. This will be an even number. For more information on this flash procedure refer to Passenger Presence System Flash Code Procedures .

AIR BAG Indicator

The AIR BAG indicator, located in the instrument panel cluster (IPC) is used to notify the driver of supplemental inflatable restraint (SIR) system malfunctions and to verify that the sensing and diagnostic module (SDM) is communicating with the IPC. When the ignition is turned ON, the SDM is supplied with ignition positive voltage. The SDM requests the IPC to flash the AIR BAG indicator seven times. While flashing the indicator, the SDM conducts test on all SIR system components and circuits. If no malfunctions are detected the SDM will communicate with the IPC through the class 2 serial data circuit and command the AIR BAG indicator OFF. The SDM provides continuous monitoring of the air bag circuits by conducting a sequence of checks. If a malfunction is detected the SDM will store a diagnostic trouble code (DTC) and command the IPC to turn the AIR BAG indicator ON via class 2 serial data and a SERVICE AIR BAG message will be display on the driver information center (DIC). The presence of a SIR system malfunction could result in non-deployment of the air bags or deployment in conditions less severe than intended. The AIR BAG indicator and the SERVICE AIR BAG message on the DIC will remain ON until the malfunction has been repaired.

Dual Stage Inflator Modules

Dual stage inflator modules contain a housing, inflatable air bag, 2 initiating devices, canister of gas generating material and, in some cases, stored compressed gas. The 2 initiators are part of the frontal deployment loop. The function of the frontal deployment loops are to supply current through the steering wheel and instrument panel (I/P) inflator modules to deploy the air bags. The inflator modules have 2 stages of deployment, which varies the amount of restraint to the occupant according to the collision severity. For moderate frontal collisions the inflator modules deploy at less than full deployment (low deployment) which consists of stage 1 of the inflator module. For more severe frontal collisions a full deployment is initiated which consists of stage 1 and stage 2 of the inflator module. The current passing through the initiators ignites the material in the canister producing a rapid generation of gas and is some cases, the release of compressed gas. The gas produced from this reaction rapidly inflates the air bag. Once the air bag is inflated it quickly deflates through the air bag vent holes and/or the bag fabric.

Each dual stage inflator modules is equipped with a shorting bar located in the connector(s) of the module. The shorting bar shorts the inflator module deployment loop circuitry to prevent unwanted deployment of the air bag when it is disconnected.

Inflatable Restraint Steering Wheel Module Coil

The steering wheel module coil is attached to the steering column and is located under the steering wheel. The steering wheel module coil consists of 2 or more current-carrying coils. The coils allow the rotation of the steering wheel while maintaining continuous electrical contact between the driver deployment loop and the steering wheel module. Two or four, if equipped with dual stage air bags, coil wires are used for the steering wheel module deployment loop. Additional coil wires are used for accessories attached to the steering wheel depending on the vehicle model. The steering wheel module coil connector is located near the base of the steering column. The connector contains a shorting bar that shorts the steering wheel module coil deployment loop circuitry to prevent unwanted deployment of the air bag when servicing the inflator module.

Inflatable Restraint Front End Sensor

The front end sensor also known as the Electronic Frontal Sensor (EFS) is equipped on vehicles to supplement the SIR system performance. The front end sensor is an electronic sensor (accelerometer) and is not part of the deployment loops, but instead provides an input to the sensing and diagnostic module (SDM). The front end sensor can assist in determining the severity of some frontal collisions. The SDM contains a microprocessor which performs calculations using the measured accelerations and compares these calculations to a value stored in memory. When the generated calculations exceed the stored value, the SDM will cause current to flow through the frontal deployment loops deploying the frontal air bags.

Inflatable Restraint Seat Belt Pretensioner

The seat belt pretensioner modules contain a housing, an initiating device, canister of gas generating material. The initiator is part of the seat belt pretensioner deployment loop. When the vehicle is involved in a collision of sufficient force, the sensing and diagnostic module (SDM) will cause current to flow through the deployment loops to the initiator. Current passing through the initiator ignites the material in the canister producing a rapid generation of gas and the release of compressed gas, if present. The gas produced from this reaction rapidly shortens the seat belt buckle height.

Each seat belt pretensioner is equipped with a shorting bar located on the connector of the pretensioner. The shorting bar shorts the seat belt pretensioner deployment loop circuitry to prevent unwanted deployment of the pretensioner when servicing the seat belt pretensioner.

Inflatable Restraint Wiring Harness

The inflatable restraint wiring harnesses connect the inflators modules, sensing and diagnostic module (SDM), deployment loops and class 2 serial data together using weather pack connectors. The deployment loops connectors for the supplemental inflatable restraint (SIR) system are yellow in color for easy identification. When repairing the SIR wiring harnesses follow the proper testing and wiring repair procedures listed in this manual. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Steering Column and Wheel

The steering wheel and columns are designed to absorb energy when driver contact is made with the steering wheel or inflated air bag. In a frontal collision the driver may come in contact with the steering wheel directly or load the steering wheel and column through the inflated air bag. When the driver applies load to the air bag or the steering wheel the column will compress downward absorbing some of the impact, helping to reduce bodily injuries to the driver. The steering wheel and column must be inspected for damages after a collision.

Knee Bolster

The knee bolsters are designed to help restrain the lower torso of front seat occupants by absorbing the energy through the front seat occupants upper legs. In a frontal collision the front seat occupant legs may come in contact with the knee bolsters. The knee bolsters are designed to crush or deform, absorbing some of the impact, which helps to reduce bodily injuries. The driver and passenger knee bolsters are located in the lower part of the instrument panel and must be inspected for damages after a collision.

Side SIR System Description

The side supplemental inflatable restraint (SIR) system consists of the following components

1. AIR BAG indicator located in the instrument panel cluster (IPC)
2. Inflatable restraint sensing and diagnostic module (SDM)
3. Inflatable restraint side impact sensors (SIS) (left/right)
4. Inflatable restraint roof rail modules (left/right)
5. Inflatable restraint wiring harnesses

The roof rail modules are located under the headliner extending from the front windshield pillar to the rear window pillar. The roof rail modules contain a housing, inflatable air bag, initiating device and a canister of gas generating material. The initiator is part of the roof rail module deployment loop. When a side impact of sufficient force occurs the SIS detects the impact and sends a signal to the SDM. The SDM compares the signal received from the SIS to a value stored in memory. When the generated signal exceeds the stored value, the SDM will cause current to flow through the roof rail air bags deployment loop. The SDM, roof rail modules and the connecting wires makeup the side deployment loops. The SDM continuously monitors the deployment loops for malfunctions and turns the AIR BAG indicator ON if a fault is present.

Each roof rail module is equipped with a shorting bar located on the connector of the module. The shorting bar shorts the roof rail modules deployment loop circuitry to prevent unwanted deployment of the air bag when servicing the inflator module.

Inflatable Restraint Side Impact Sensor (SIS)

The side impact sensor (SIS) contains a sensing device which monitors vehicle acceleration and velocity changes to detect side collisions that are severe enough to warrant air bag deployment. The SIS is not part of the deployment loop, but instead provides an input to the sensing and diagnostic module (SDM). The SDM contains a microprocessor that performs calculations using the measured accelerations and compares these calculations to a value stored in memory. When the generated calculations exceed the stored value, the SDM will cause current to flow through the deployment loops deploying the roof rail air bags.

Special Tools

Special Tools Illustration Tool Number/Description J 38715-A Driver/Passenger SIR Load Tool J 38826 SIR Deployment Harness J 39401-B SIR Deployment Fixture J 44298 Driver Air Bag Removal Tool

See also:
• Diagnostic System Check - Vehicle
• Diagnostic Trouble Code (DTC) List - Vehicle
• Circuit Testing
• Connector Repairs
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Diagnostic Repair Verification
• Control Module References
• Power Seat Systems Connector End Views
• Checking Aftermarket Accessories
• Trim Panel Replacement - Rear Quarter Upper
• Trim Panel Replacement - Side Front Door
• Closeout/Insulator Panel Replacement - Left
• Fastener Notice
• SIR Caution
• Radiator Air Baffle and Deflector Replacement - Upper
• SIR Inflator Module Handling and Storage Caution
• Steering Wheel Replacement
• Steering Column Accident Damage Inspection
• Operational and Functional Checks
• SIR Inflator Module Disposal Caution
• SIR Deployed Inflator Modules Are Hot Caution
• SIR Inflatable Module Deployment Outside Vehicle Caution
• SIR Disabling and Enabling Zones
• DTC B0012, B0013, B0014, B0016, B0017 or B0018
• SIR Connector End Views
• Special Tools
• Repair Verification
• SIR Service Precautions
• SIR Zone Identification Views
• Fastener Tightening Specifications
• Tools Required