Supplemental Inflatable Restraint System GMC Sierra 2500

Fastener Tightening Specifications

Fastener Tightening Specifications

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

SIR Identification Views

The SIR Identification Views shown below illustrate the approximate location of all SIR components available for the vehicle. This will assist in disabling and enabling the SIR system, refer to SIR Disabling and Enabling .

Scheme 6

Diagnostic Code Index

DIAGNOSTIC CODE INDEX

Diagnostic Instructions

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category

Diagnostic Fault Information

Circuit/System Description

During a 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 wheel air bag. The inflatable restraint sensing and diagnostic module 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 air bag coil connector which will short together both steering wheel air bag stage 1 high control circuit and steering wheel air bag stage 1 low control circuit and both steering wheel air bag stage 2 high control circuit and steering wheel air bag stage 2 low control circuit when the connector is disconnected. This will help to prevent unwanted deployment of the steering wheel air bag during servicing.

Conditions for Running the DTC

Ignition voltage is between 9-16 V.

Conditions for Setting the DTC

B0012 01 stage 1 or B0013 01 stage 2

The steering wheel air bag deployment loop is shorted to voltage for 2 seconds.

B0012 02 stage 1 or B0013 02 stage 2

The steering wheel air bag deployment loop is shorted to ground for 2 seconds.

B0012 04 stage 1 or B0013 04 stage 2

The steering wheel air bag deployment loop is open for 2 seconds.

B0012 0D stage 1 or B0013 0D stage 2

The steering wheel air bag deployment loop resistance is greater than 4.4 ohms for 2 seconds.

B0012 0E stage 1 or B0013 0E stage 2

The steering wheel air bag deployment loop resistance is less than 1.7 ohms for 2 seconds.

Action Taken When the DTC Sets

1. The inflatable restraint sensing and diagnostic module requests the instrument cluster to illuminate the AIR BAG indicator.
2. The inflatable restraint sensing and diagnostic module will store a DTC, however if an event occurs the system will still attempt deployment.

Conditions for Clearing the DTC

1. The condition for setting the DTC is no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Diagnostic Aid

Note. The following diagnostic aids apply for both current and history DTCs.

A worn steering wheel air bag coil can cause a repeated history DTC to set. To verify this condition, turn the steering wheel 360 degrees in one direction then back 360 degrees in the other direction, multiple times, while viewing the scan tool Deployment Loop Resistance parameters.

An incorrectly installed connector position assurance (CPA) or incorrectly seated connector can cause a shorting bar to short both control circuits together. Check the connectors and CPAs if a DTC with symptom byte 02 or 0E is set, to ensure the shorting bars are not causing the circuits to be shorted together. Shorting bars are used in the locations listed below

1. Steering wheel air bag assembly
2. Steering wheel air bag coil assembly
3. Inline harness connectors
4. Harness side of the inflatable restraint sensing and diagnostic module connector

Terminal fretting or incorrectly seated connector can cause an open/high resistance condition. Check the circuit terminals for fretting or incorrectly seated connector if a DTC with symptom byte 04 or 0D is set.

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
4. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38125-580 Terminal Release Tool Kit

Circuit/System Verification

Note. Refer to SIR Service Precautions . Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of the affected component/connector. Driver steering wheel air bag Driver steering wheel air bag coil Inflatable restraint sensing and diagnostic module Air bag wiring harness connector Inflatable restraint sensing and diagnostic module wiring harness connector The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly. Replace any CPA that is damaged or missing. If the condition is intermittent or cannot be duplicated, disconnect the connectors and add dielectric grease / lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087). This procedure will correct the high resistance condition due to terminal fretting corrosion.

1. Verify the appropriate scan tool Deployment Loop Resistance parameters stay consistently between 2.1-4.0 ohms without any spikes or dropouts while turning the steering wheel 360 degrees in one direction then back 360 degrees in the other direction. If less than 2.1 ohms or greater than 4.0 ohms Refer to Circuit/System Testing below. If there are spikes or dropouts Replace the steering wheel air bag coil. If between 2.1-4.0 ohms without any spikes or dropouts
2. Verify DTC B0012 or B0013 is only set as a history DTC. If the DTC is set as current Refer to Circuit/System Testing below. If the DTC is set as history
3. Verify the scan tool Deployment Loop Resistance parameters stay consistently between 2.1-4.0 ohms without any drop outs or spikes while moving the harness near each connector listed below. Steering wheel air bag coil Steering wheel air bag. Any inline harness connector Inflatable restraint sensing and diagnostic module If the reading is erratic while moving the harness, perform the following Inspect each connector terminal for damage or corrosion and repair as necessary. Apply dielectric grease / lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087) to each connector terminal. Ensure each connector and CPA is correctly seated. If between 2.1-4.0 ohms without any spikes or dropouts
4. All OK.

Circuit/System Testing

1. Ignition OFF, disconnect the scan tool and disconnect the appropriate harness connector listed below at the steering wheel air bag. It may take up to 2 minutes for all vehicle systems to power down. DTC B0012 connector X1 DTC B0013 connector X2
2. Test for greater than 25 ohms between the control circuit terminal 1 and the control circuit terminal 2. If 25 ohms or less Disconnect the X1 harness connector at the inflatable restraint sensing and diagnostic module. NOTE: Some connectors may be equipped with shorting bars as a safety component to prevent accidental inflator deployment. When testing on a connector with shorting bars, the shorting bars must be disabled to ensure accurate test results. Insert an appropriate pick from EL-38125-580 and depress the shorting bars above the appropriate terminals. This will lift the shorting bar from the terminal and allow accurate test results. Take care not to damage the connector, shorting bar, or terminal when depressing the shorting bar. Test for infinite resistance between the two control circuits. If less than infinite resistance, repair the short between the two circuits. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
3. Ignition ON.
4. Test for less than 11 V between each control circuit terminal listed below and ground: Control circuit terminal 1 Control circuit terminal 2 If 11 V or greater Ignition OFF, disconnect the X1 harness connector at the inflatable restraint sensing and diagnostic module, ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the inflatable restraint sensing and diagnostic module. If less than 11 V
5. Ignition OFF.
6. Test for greater than 25 ohms between each control circuit terminal listed below and ground: Control circuit terminal 1 Control circuit terminal 2 If 25 ohms or less Disconnect the X1 harness connector at the inflatable restraint sensing and diagnostic module. NOTE: Some connectors may be equipped with shorting bars as a safety component to prevent accidental inflator deployment. When testing on a connector with shorting bars, the shorting bars must be disabled to ensure accurate test results. Insert an appropriate pick from EL-38125-580 and depress the shorting bars above the appropriate terminals. This will lift the shorting bar from the terminal and allow accurate test results. Take care not to damage the connector, shorting bar, or terminal when depressing the shorting bar. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
7. Install a 3 A fused jumper wire between the control circuit terminal 1 and the control circuit terminal 2, ignition ON.
8. Verify the scan tool Deployment Loop Resistance parameter is consistently less than 2 ohms while turning the steering wheel 360 degrees in one direction then back 360 degrees in the other direction. If the reading is erratic while turning the steering wheel Replace the steering wheel airbag coil. If 2 ohms or greater Ignition OFF, disconnect the X1 harness connector at the inflatable restraint sensing and diagnostic module. Test for less than 2 ohms in the steering wheel airbag coil and each control circuit end to end. If 2 ohms or greater, replace the coil or repair the open/high resistance in the circuit. If less than 2 ohms, replace the inflatable restraint sensing and diagnostic module. If less than 2 ohms
9. Ignition OFF, connect the harness connector at the steering wheel air bag, press in the CPA (if equipped) until an audible and/or tactile click is heard.
10. Ignition ON, clear DTCs. Operate the vehicle within the Conditions for Running the DTC.
11. Verify DTC B0012 or B0013 is not set. If DTC B0012 or B0013 is set Replace the steering wheel air bag. If DTC B0012 or B0013 is not set
12. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

1. «Steering Wheel Airbag Coil Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system__steering-wheel-airbag-coil-replacement)
2. «Steering Wheel Inflatable Restraint Module Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
3. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
4. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for inflatable restraint sensing and diagnostic module replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

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 air bag. A shorting bar (if equipped) is located in the connector.

Ignition voltage is between 9-16 V.

B0014 01, B0015 01, B0016 01, B0019 01, B0020 01, B0021 01, B0022 01, B0023 01

The air bag or pretensioner high and/or low circuit is shorted to voltage for 120 milliseconds.

B0014 02, B0015 02, B0016 02, B0019 02, B0020 02, B0021 02, B0022 02, B0023 02

The air bag or pretensioner high and/or low circuit is shorted to ground for 120 milliseconds.

B0014 04, B0015 04, B0016 04, B0019 04, B0020 04, B0021 04, B0022 04, B0023 04

The air bag or pretensioner high and/or low circuit is open for 120 milliseconds.

B0014 0D, B0015 0D, B0016 0D, B0019 0D, B0020 0D, B0021 0D, B0022 0D, B0023 0D

The air bag or pretensioner deployment loop resistance is greater than 3.9 ohms for 120 milliseconds.

B0014 0E, B0015 0E, B0016 0E, B0019 0E, B0020 0E, B0021 0E, B0022 0E, B0023 0E

The air bag or pretensioner deployment loop resistance is less than 1.1 ohms for 120 milliseconds.

1. The inflatable restraint sensing and diagnostic module requests the instrument cluster to illuminate the SIR system AIR BAG indicator.
2. The inflatable restraint sensing and diagnostic module will store a DTC, however if an event occurs the system will still attempt deployments.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 fault-free ignition cycles have occurred.

Note. The following diagnostic aids apply for both current and history DTCs.

An incorrectly installed CPA or incorrectly seated connector can cause a shorting bar to short both control circuits together. Check the connectors and CPAs if a DTC with symptom byte 02 or 0E is set, to ensure the shorting bars are not causing the circuits to be shorted together. Shorting bars are used in the locations listed below

1. Passenger instrument panel air bag
2. Driver and passenger seat side air bags
3. Left and right roof rail air bags
4. Left and right pretensioners
5. Inline connectors - on the side of the harness connector
6. Harness side of the inflatable restraint sensing and diagnostic module connector

Terminal fretting or incorrectly seated connector can cause an open/high resistance condition. Check the circuit terminals for fretting or incorrectly seated connector if a DTC with symptom byte 04 or 0D is set. If DTCs of deployment loops which are in the seat DTC B0014 and B0021, can occur because of stress or damage to the harness due to seat movement. Move the seat to the full extend of travel while using the scan tool to observe deployment type loop parameters.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Special Tools

EL-38125-580 Terminal Release Tool Kit

Note. Refer to SIR Service Precautions . Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of the affected component/connector. Seat belt pretensioner Passenger instrument panel air bag Side air bag Roof rail air bag Inflatable restraint sensing and diagnostic module Seat belt pretensioner wiring harness connector Passenger instrument panel air bag wiring harness connector Seat side air bag wiring harness connector Roof rail air bag wiring harness connector Inflatable restraint sensing and diagnostic module wiring harness connector The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly. If the condition is intermittent or cannot be duplicated, disconnect the connectors and add dielectric grease / lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087). This procedure will correct the high resistance condition due to terminal fretting corrosion.

1. Verify the scan tool Deployment Loop Resistance 1 and 2 parameters stay consistently between 2.1 and 4.0 ohms without any spikes or dropouts while moving the harness near each connector listed below: Passenger instrument panel air bag Roof rail air bag - left Roof rail air bag - right Side air bag Seat belt retractor pretensioner Any inline harness Inflatable restraint sensing and diagnostic module If less than 2.1 or greater than 4.0 ohms Refer to Circuit/System Testing below. If there are spikes or dropouts, perform the following Inspect each connector terminal and harness for damage or corrosion and repair as necessary Insure each connector and CPA is correctly seated. If within 2.1 and 4.0 ohms without any spikes or dropouts
2. All OK

DTC B0014-B0018 or B0021-B0045

1. Ignition OFF.
2. Disconnect the scan tool.
3. Disconnect the appropriate harness connector listed below: Roof rail air bag - left Roof rail air bag - right Side air bag Seat belt retractor pretensioner
4. Wait for 120 seconds.
5. Test for greater than 25 ohms between the control circuit terminals A (Regular cab) or 1 (Extended and Crew Cab) and B (Regular cab) or 2 (Extended and Crew Cab). If 25 ohms or less Disconnect the harness connector at the inflatable restraint sensing and diagnostic module. NOTE: Some connectors may be equipped with shorting bars as a safety component to prevent accidental inflator deployment. When testing on a connector with shorting bars, the shorting bars must be disabled to ensure accurate test results. Insert an appropriate pick from EL-38125-580 and depress the shorting bars above the appropriate terminals. This will lift the shorting bar from the terminal and allow accurate test results. Take care not to damage the connector, shorting bar, or terminal when depressing the shorting bar. Test for infinite resistance between the two control circuits. If less than infinite resistance, repair the short between the two circuits. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
6. Ignition ON.
7. Test for less than 11 V between the appropriate control circuit terminals listed below and ground: Roof rail module high control circuit terminal 1 Roof rail module high control circuit terminal 2 Seat side air bag control circuit terminal 1 Seat side air bag control circuit terminal 2 Seat belt retractor pretensioner control circuit terminal 1 Seat belt retractor pretensioner control circuit terminal 2 If 11 V or greater Ignition OFF. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the K36 inflatable restraint sensing and diagnostic module. If less than 11 V
8. Ignition OFF.
9. Test for greater than 25 ohms between the appropriate control circuit terminals listed below and ground: Roof rail module high control circuit terminal 1 Roof rail module high control circuit terminal 2 Seat side air bag control circuit terminal 1 Seat side air bag control circuit terminal 2 Seat belt retractor pretensioner control circuit terminal 1 Seat belt retractor pretensioner control circuit terminal 2 If 25 ohms or less Disconnect the harness connector at the inflatable restraint sensing and diagnostic module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
10. Ignition OFF.
11. Install a 3 A fused jumper wire between the control circuit terminals A (Regular cab) or 1 (Extended and Crew Cab) and B (Regular cab) or 2 (Extended and Crew Cab).
12. Ignition ON.
13. Verify the scan tool Deployment Loop Resistance parameter is less than 2 ohms. If 2 ohms or greater Ignition OFF. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module. Test for less than 2 ohms in each control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the K36 inflatable restraint sensing and diagnostic module. If less than 2 ohms
14. Ignition OFF, connect the harness connector at the roof rail air bag - left, roof rail air bag - right, side air bag or seat belt retractor pretensioner, press in the CPA (if equipped) until an audible and/or tactile click is heard.
15. Ignition ON, clear DTCs. Operate the vehicle within the Conditions for Running the DTC.
16. Verify DTC B0014-B0018 or B0021-B0045 is not set. If DTC B0014-B0018 or B0021-B0045 is set Replace the roof rail air bag - left, roof rail air bag - right, side air bag or seat belt retractor pretensioner. If DTC B0014-B0018 or B0021-B0045 is not set
17. All OK.

DTC B0019-B0020

1. Ignition OFF.
2. Disconnect the scan tool.
3. Disconnect the harness connector X200.
4. Test for greater than 25 ohms between the inflatable restraint I/P module stage 1 control circuit terminals X200 terminal A1 and A2. If 25 ohms or less Disconnect the harness connector at the inflatable restraint sensing and diagnostic module. NOTE: Some connectors may be equipped with shorting bars as a safety component to prevent accidental inflator deployment. When testing on a connector with shorting bars, the shorting bars must be disabled to ensure accurate test results. Insert an appropriate pick from EL-38125-580 and depress the shorting bars above the appropriate terminals. This will lift the shorting bar from the terminal and allow accurate test results. Take care not to damage the connector, shorting bar, or terminal when depressing the shorting bar. Test for infinite resistance between the two control circuits. If less than infinite resistance, repair the short between the two circuits. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
5. Test for greater than 25 ohms between the inflatable restraint I/P module stage 2 control circuit terminals X200 terminal B1 and B2. If 25 ohms or less Disconnect the harness connector at the inflatable restraint sensing and diagnostic module. NOTE: Some connectors may be equipped with shorting bars as a safety component to prevent accidental inflator deployment. When testing on a connector with shorting bars, the shorting bars must be disabled to ensure accurate test results. Insert an appropriate pick from EL-38125-580 and depress the shorting bars above the appropriate terminals. This will lift the shorting bar from the terminal and allow accurate test results. Take care not to damage the connector, shorting bar, or terminal when depressing the shorting bar. Test for infinite resistance between the two control circuits. If less than infinite resistance, repair the short between the two circuits. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
6. Ignition ON.
7. Test for less than 11 V between the control circuit terminals listed below and ground: X200 control circuit terminal A1 X200 control circuit terminal A2 X200 control circuit terminal B1 X200 control circuit terminal B2 If 11 V or greater Ignition OFF. Disconnect the harness connector at the inflatable restraint sensing and diagnostic module. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the inflatable restraint sensing and diagnostic module. If less than 11 V
8. Test for greater than 25 ohms between the control circuit terminals listed below and ground: X200 control circuit terminal A1 X200 control circuit terminal A2 X200 control circuit terminal B1 X200 control circuit terminal B2 If 25 ohms or less Disconnect the harness connector at the inflatable restraint sensing and diagnostic module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 25 ohms
9. Ignition OFF.
10. Connect harness connector X200.
11. Disconnect the inflatable restraint I/P module connector.
12. Ignition ON.
13. Test for less than 11 V between the control circuit terminals listed below and ground: I/P module- stage 1- high control circuit terminal A1 (10 series without MEX) or A (without 10 series or with MEX) X1 I/P module- stage 1- low control circuit terminal A2 (10 series without MEX) or B (without 10 series or with MEX) X1 I/P module- stage 2- high control circuit terminal B1 X1 I/P module- stage 2- low control circuit terminal B2 X1 If 11 V or greater Repair the short to voltage on the circuit. If less than 11 V
14. Ignition OFF.
15. Test for greater than 25 ohms between the control circuit terminals listed below and ground: I/P module- stage 1- high control circuit terminal A1 (10 series without MEX) or A (without 10 series or with MEX) X1 I/P module- stage 1- low control circuit terminal A2 (10 series without MEX) or B (without 10 series or with MEX) X1 I/P module- stage 2- high control circuit terminal B1 X1 I/P module- stage 2- low control circuit terminal B2 X1 If 25 ohms or less Repair the short to ground on the circuit. If greater than 25 ohms
16. Ignition OFF.
17. Test for less than 5 ohms between the control circuit terminals listed below: X200 control circuit terminal A1 and I/P module- stage 1- high control circuit terminal A1 (10 series without MEX) or A (without 10 series or with MEX) X1 X200 control circuit terminal A2 and I/P module- stage 1- low control circuit terminal A2 (10 series without MEX) or B (without 10 series or with MEX) X1 X200 control circuit terminal B1 and I/P module- stage 2- high control circuit terminal B1 X1 X200 control circuit terminal B2 and I/P module- stage 2- low control circuit terminal B2 X1 If greater than 5 ohms Repair the open/high resistance in the circuit. If 5 ohms or less
18. Ignition OFF, connect the harness connector at the inflatable restraint I/P module, press in the CPA (if equipped) until an audible and/or tactile click is heard.
19. Ignition ON, clear DTCs. Operate the vehicle within the Conditions for Running the DTC.
20. Verify DTC B0019 or B0020 is not set. If DTC B0019 or B0020 is set Replace the inflatable restraint I/P module. If DTC B0019 or B0020 is not set
21. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Instrument Panel Inflatable Restraint Module Replacement (Without SLT)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Instrument Panel Inflatable Restraint Module Replacement (With SLT)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
3. «Steering Wheel Inflatable Restraint Module Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
4. «Steering Wheel Airbag Coil Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system__steering-wheel-airbag-coil-replacement)
5. «Inflatable Restraint Side Impact Sensor Replacement (Crew Cab, Rear Door)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Inflatable Restraint Side Impact Sensor Replacement (Crew Cab/Extended Cab/Regular Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Inflatable Restraint Side Impact Sensor Replacement (Extended Cab, Rear Door)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
6. «Roof Side Rail Inflatable Restraint Module Replacement (Regular Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Roof Side Rail Inflatable Restraint Module Replacement (Extended Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Roof Side Rail Inflatable Restraint Module Replacement (Crew Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
7. «Seat Belt Retractor Pretensioner Replacement - Front (Crew Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Seat Belt Retractor Pretensioner Replacement - Front (Extended Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Seat Belt Retractor Pretensioner Replacement - Front (Regular Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
8. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for SDM replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using the diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The Inflatable Restraint Sensing and Diagnostic Module (SDM) senses vehicle impacts and provides deployment signals to the air bags and anchor and/or retractor pretensioners when warranted. The Inflatable Restraint Sensing and Diagnostic Module sets DTC B0052 after each command for deployment. DTC B0052 will latch and not clear after 3 commanded deployments by the Inflatable Restraint Sensing and Diagnostic Module. Therefore the Inflatable Restraint Sensing and Diagnostic Module has to be replaced.

Ignition voltage is between 9-16 V.

1. The Inflatable Restraint Sensing and Diagnostic Module detects a frontal impact of sufficient force to warrant deployment of the frontal air bags.
2. The Inflatable Restraint Sensing and Diagnostic Module detects a side impact or rollover (if equipped) of sufficient force to warrant deployment of a seat side air bag and/or roof rail air bag.

The Inflatable Restraint Sensing and Diagnostic Module requests the instrument cluster to illuminate the AIR BAG indicator.

1. DTC B0052 00 is a DTC that may be cleared with a scan tool without replacing the Inflatable Restraint Sensing and Diagnostic Module. This DTC will not clear if deployment has been commanded more then two times, and the Inflatable Restraint Sensing and Diagnostic Module would have to be replaced.
2. DTC B0052 56 is a latched DTC. The DTC cannot be cleared with the scan tool. Replacement of the Inflatable Restraint Sensing and Diagnostic Module is required.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
4. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Verify that DTC B0052 00 is not set. If DTC B0052 00 is set Clear the DTC. If the DTC will not clear, replace the K36 Inflatable Restraint Sensing and Diagnostic Module. If DTC B0052 00 is not set
2. Verify that DTC B0052 56 is not set. If DTC B0052 56 is set Replace the K36 Inflatable Restraint Sensing and Diagnostic Module. If DTC B0052 56 is not set
3. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for Inflatable Restraint Sensing and Diagnostic Module control module replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The inflatable restraint seat belt tension sensor is a 3-wire potentiometer mounted on the buckle side of the passenger seat belt and provides an input to the passenger presence system (PPS). When an infant car seat is properly restrained on the front passenger seat, the seat belt is tightly secured through the car seat. The seat belt pulls on the tension sensor and changes the voltage signal to the PPS module. The PPS module monitors the belt tension sensor signal circuit and if a fault is detected, DTC will be set. When the PPS module detects this DTC it will send out a serial data message and the SDM will notify the customer of the enable/disable status by illuminating the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators. The SDM will then suppress the deployment of the passenger instrument panel air bag and illuminate the AIR BAG indicator.

Ignition voltage is between 9-16 volts.

1. The PPS module detects the voltage at the passenger seat belt tension sensor signal circuit is less than 0.5 volt or greater than 4.5 volts for 1 second.
2. The PPS module detects the voltage at the passenger seat belt tension sensor voltage reference circuit is less than 4.5 volts or greater than 9.1 volts for 1 second.
3. The PPS module detects the amperage at the passenger seat belt tension sensor low reference circuit is 25 MA or greater for 1 second.

1. The PPS module will set a DTC, and then communicate with the SDM.
2. The SDM will set DTC B0081 0F.
3. The SDM disables the passenger instrument panel air bag.
4. The PPS module will illuminate the passenger air bag status OFF indicator.
5. The SDM requests the instrument panel cluster (IPC) to illuminate the AIRBAG indicator.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Diagnostic Aids

Inspect the passenger seat belt tension sensor signal, voltage reference, and low reference circuits carefully for cutting and/or chafing.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition OFF, disconnect the harness connector at the passenger seat belt tension sensor X2 and inspect the component and harness sides for damage or corrosion. If damage or corrosion is found, repair or replace as necessary.
2. Ignition ON, test for 4.5-5.5 volts between the passenger seat belt tension sensor voltage reference circuit terminal A X2 and ground. If less that the specified range, test the voltage reference circuit for open/high resistance or a short to ground. If the circuit tests normal, replace the PPS module. If greater that the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the PPS module.
3. Ignition OFF, remove the AIR BAG BATT Fuse in the underhood fuse block. Test for less than 2.0 ohms between the passenger seat belt tension sensor low reference terminal B X2 and ground. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the PPS module.
4. Ignition OFF, disconnect the harness connector at the PPS module.
5. Ignition ON, test for infinite resistance between the passenger seat belt tension sensor signal circuit terminal C X2 and ground. If less than the specified value, test the signal circuit for a short to ground.
6. Ignition ON, test for less than 1 volt between the passenger seat belt tension sensor signal circuit terminal C X2 and ground. If greater than the specified range, test the circuit for a short to voltage
7. Test for less than 1 ohm between the PPS module signal circuit terminal 6 (-HP2/Z75+HP2) and the passenger seat belt tension sensor terminal C X2. If greater than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the PPS module.
8. If all circuits test normal, replace the passenger seat belt buckle which includes the seat belt tension sensor.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Front Seat Belt Buckle Replacement»(/gmc/sierra-2500/2012-2012/remont/restraints-control-systems/#seat-belt-system)
3. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for PPS replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using the diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The passenger presence system (PPS) uses a silicone filled sensor pad located underneath the passenger seat foam cushion and is connected by a hose clamp to a passenger presence sensor. The weight of the occupant sitting in the front passenger seat is measured as a pressure change within the bladder by the passenger presence sensor. The passenger presence sensor is a 3-wire sensor consisting of a power, ground, and signal circuit. The PPS continually monitors itself and if a fault in this circuit occurs, a DTC will set in the passenger presence module. When the Inflatable Restraint Sensing and Diagnostic Module (SDM) detects this DTC within the passenger presence module, it will notify the customer of the enable/disable status by illuminating the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators. Then the passenger presence module will communicate to the Inflatable Restraint Sensing and Diagnostic Module through serial data communications that a PPS fault is present. The Inflatable Restraint Sensing and Diagnostic Module will then suppress the deployment of the passenger instrument panel air bag and then illuminate the AIR BAG indicator.

Ignition voltage is between 9-16 volts.

1. The passenger presence module detects the voltage at the passenger presence sensor signal is less than 0.5 volt or greater than 4.5 volts for 500 milliseconds.
2. The passenger presence module detects the voltage at the passenger presence sensor 5 volt reference is less than 4.5 volts or greater than 9.1 volts for 500 milliseconds.
3. The passenger presence module detects the amperage at the passenger presence sensor low reference is 25 mA or greater for 500 milliseconds.

1. The passenger presence module will set a DTC, and then communicate with the Inflatable Restraint Sensing and Diagnostic Module.
2. The Inflatable Restraint Sensing and Diagnostic Module disables the passenger instrument panel air bag deployment loop.
3. The passenger presence module will illuminate the passenger air bag status OFF indicator.
4. The Inflatable Restraint Sensing and Diagnostic Module requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

1. If either the Inflatable Restraint Sensing and Diagnostic Module or PPS were replaced verify that the correct part numbers were used for the vehicle application.
2. If this DTC is set as either current or history it may have been caused by an electronic device. If an electronic device (Computers, MP3 Players, Cell Phones, Diagnostic Scan Tool, etc.) was placed on the passenger seat the passenger presence module may command the passenger air bag indicator to turn on and/or command the passenger seat belt indicator to turn on. Make sure there are no objects on the passenger seat and clear the DTCs. If this DTC resets then perform this diagnostic. If the DTC does not reset there is no further work needed on the passenger presence system.
3. If this DTC is set as either current or history it may have been caused by an aftermarket seat heater. The aftermarket seat heater may command the passenger air bag indicator to turn on and/or command the passenger seat belt indicator to turn on. Remove the aftermarket seat heater from the passenger seat and clear the DTCs. If this DTC resets then perform this diagnostic. If the DTC does not reset there is no further work needed on the passenger presence system.

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition OFF, disconnect the harness connector at the Passenger Presence Sensor and inspect the component and harness sides for damage or corrosion. If damage or corrosion is found, repair or replace as necessary.
2. Ignition ON, test for 4.5-5.5 volts between the voltage reference circuit terminal 1 (HP2) or A (without HP2) and ground. If less that the specified range, test the voltage reference circuit for open/high resistance or a short to ground. If the circuit tests normal, replace the passenger presence module. If greater that the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the passenger presence module.
3. Ignition OFF, doors open, remove the AIR BAG BATT Fuse. Test for less than 2.0 ohms between low reference terminal 3 (HP2) or C (without HP2) and ground. If greater than the specified range, test the low reference circuit for open/high resistance. If the circuit tests normal, replace the Passenger Presence System.
4. Ignition OFF, disconnect the harness connector at the Passenger Presence Module.
5. Test for infinite resistance between the signal circuit terminal 6 and ground. If less than the specified value, test the signal circuit for a short to ground.
6. Ignition ON, test for less than 1 volt between the signal circuit terminal 6 and ground. If greater than the specified range, test the signal circuit for a short to voltage.
7. Ignition OFF, test for less than 2.0 ohms between the Passenger Presence Module terminal 6 and the Passenger Presence Sensor terminal 2 (HP2) or B (without HP2). If greater than the specified range, test the signal circuit for open/high resistance.
8. If all circuits test normal, replace the Passenger Presence System.

Perform the Diagnostic Repair Verification after completing the repair.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Passenger Presence System replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category

The seat position sensor is used to determine the proximity of a front driver or passenger seat position with respect to the frontal air bag. There are two states of seat position, forward and rearward. The seat position sensor interfaces with the Inflatable Restraint Sensing and Diagnostic Module (SDM) and allows the Inflatable Restraint Sensing and Diagnostic Module to disable stage 2 of the frontal air bag for a front seat that is forward of the forward/rearward point in seat track. The seat position sensor provides 2 current ranges, one range for the forward seat position and one for rearward seat position. When the Inflatable Restraint Sensing and Diagnostic Module receives input from a seat position sensor that the seat is rearward, and the Inflatable Restraint Sensing and Diagnostic Module will not disable stage 2 deployment. When the seat is forward, the Inflatable Restraint Sensing and Diagnostic Module will disable stage 2 deployment. The Inflatable Restraint Sensing and Diagnostic Module monitors the seat position sensor circuit and if a fault is detected, the Inflatable Restraint Sensing and Diagnostic Module will set code B0079 or B0080 and disable stage 2 frontal deployment.

Ignition voltage is between 9-16 V.

B0079 01, B0080 01

The Inflatable Restraint Sensing and Diagnostic Module detects the seat position sensor signal circuit is shorted to voltage for 2 seconds.

B0079 02, B0080 02

The Inflatable Restraint Sensing and Diagnostic Module detects the seat position sensor signal circuit is shorted to ground for 2 seconds.

B0079 04, B0080 04

The Inflatable Restraint Sensing and Diagnostic Module detects the seat position sensor signal circuit is open for 2 seconds.

B0079 05, B0080 05

The Inflatable Restraint Sensing and Diagnostic Module detects the seat position sensor signal circuit is open or has a high voltage condition for 2 seconds.

B0079 06, B0080 06

The Inflatable Restraint Sensing and Diagnostic Module detects the seat position sensor signal circuit is shorted to ground or an open for 2 seconds.

B0079 08, B0080 08

The Inflatable Restraint Sensing and Diagnostic Module detects an invalid signal on the seat position sensor signal circuit.

B0079 0C, B0080 0C

The Inflatable Restraint Sensing and Diagnostic Module detects a low current condition in the seat position sensor signal circuit for 2 seconds.

1. The Inflatable Restraint Sensing and Diagnostic Module defaults the seat position sensor to seat forward threshold.
2. The Inflatable Restraint Sensing and Diagnostic Module requests the instrument cluster to illuminate the AIR BAG indicator.

1. The condition for setting the DTC no longer present.
2. A history DTC will clear once 100 fault-free ignition cycles have occurred.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
4. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Verify that DTC B0079 08 or B0080 08 is not set. If the DTC is set with the symptom byte 08 Replace the appropriate seat position sensor If the DTC is not set with the symptom byte 08
2. Verify that DTC B0079 or B0080 is not set. If the DTC is set Refer to Circuit/System Testing below. If the DTC is not set
3. Ignition ON, observe the appropriate scan tool seat position sensor parameter. Verify the parameter is either forward or rearward. If the parameter is neither forward or rearward Refer to Circuit/System Testing below. If the parameter is either forward or rearward
4. With the seat un-occupied, observe the scan tool while moving the seat to the full forward and then full rearward positions. Verify the seat position sensor parameter varies between Forward and Rearward. If the parameter does not vary Refer to Circuit/System Testing below. If the parameter varies between Forward and Rearward
5. All OK.

Note. When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector: Seat position sensor Inflatable Restraint Sensing and Diagnostic Module Seat position sensor wiring harness connector Inflatable Restraint Sensing and Diagnostic Module wiring harness connector

1. Ignition OFF, disconnect the harness connector at the appropriate seat position sensor.
2. Test for less than 10 ohms between the low reference circuit terminal 1 and ground. If 10 ohms or greater Disconnect the X2 harness connector at the Inflatable Restraint Sensing and Diagnostic Module. Test for less than 2 ohms in the low reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the Inflatable Restraint Sensing and Diagnostic Module. If less than 10 ohms
3. Ignition ON, test for 4-9 V between the signal circuit terminal 2 and ground. If less than 4 V Ignition OFF. Disconnect the X2 harness connector at the Inflatable Restraint Sensing and Diagnostic Module. Test for infinite resistance between the control circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. Test for less than 2 ohms in each control circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the Inflatable Restraint Sensing and Diagnostic Module. If greater than 9 V Ignition OFF, disconnect the X2 harness connector at the Inflatable Restraint Sensing and Diagnostic Module. Ignition ON. Test for less than 1 V between the control circuit and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the Inflatable Restraint Sensing and Diagnostic Module. If within the specified range
4. Replace the Seat Position Sensor.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Inflatable Restraint Seat Position Sensor Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
2. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
3. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Inflatable Restraint Sensing and Diagnostic Module replacement, programming, and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using the diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the ignition is turned ON, the Passenger Presence Module and the Inflatable Restraint Sensing and Diagnostic Module performs tests to diagnose critical malfunctions. When the Inflatable Restraint Sensing and Diagnostic Module has completed the power-up mode, the Inflatable Restraint Sensing and Diagnostic Module will establish communication with the Passenger Presence Module. The Inflatable Restraint Sensing and Diagnostic Module will also request the instrument panel cluster (IPC) to illuminate both of the PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. If the Inflatable Restraint Sensing and Diagnostic Module determines the correct Passenger Presence Module is installed and functioning normally, the Inflatable Restraint Sensing and Diagnostic Module will illuminate the passenger air bags ON or OFF indicator based on messages from the Passenger Presence Module. The Inflatable Restraint Sensing and Diagnostic Module sends a message to the IPC to illuminate the appropriate PASSENGER AIR BAG ON/OFF indicator.

Ignition voltage is between 9-16 V.

All of the following conditions must exist for 5 seconds

B0081 00

The Inflatable Restraint Sensing and Diagnostic Module sets this DTC if there is a fault present in the Passenger Presence Module.

B0081 3A

The Inflatable Restraint Sensing and Diagnostic Module sets this DTC when the Inflatable Restraint Sensing and Diagnostic Module has received a message from the Passenger Presence Module which indicates a mismatch between the Inflatable Restraint Sensing and Diagnostic Module and Passenger Presence Module. There is either an incorrect Inflatable Restraint Sensing and Diagnostic Module or Passenger Presence Module installed on this vehicle.

B0081 4B

The Passenger Presence Module sets this DTC when the Passenger Presence Module has not learned the calibrations.

B0081 5A

The Passenger Presence Module sets this code when the Passenger Presence Module has lost communications with the Inflatable Restraint Sensing and Diagnostic Module.

1. The Inflatable Restraint Sensing and Diagnostic Module disables the passenger instrument cluster air bag.
2. The Passenger Presence Module will illuminate the Passenger Airbag On/Off indicator status as OFF.
3. When the Passenger Presence Module sets this DTC, the Passenger Presence Module communicates with the Inflatable Restraint Sensing and Diagnostic Module to turn the AIRBAG indicator on.
4. When the Inflatable Restraint Sensing and Diagnostic Module sets this DTC, the Inflatable Restraint Sensing and Diagnostic Module will turn the AIRBAG indicator on.
5. The Inflatable Restraint Sensing and Diagnostic Module requests the instrument panel cluster (IPC) to illuminate the AIRBAG indicator.

1. The condition for setting the DTC no longer exists and there is no activity on the low speed serial data circuits.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

1. If either the Inflatable Restraint Sensing and Diagnostic Module or Passenger Presence Module were replaced verify that the correct part numbers were used for the vehicle application.
2. If this DTC is set as either current or history it may have been caused by an electronic device. If an electronic device (Computers, MP3 Players, Cell Phones, Diagnostic Scan Tool, Power Inverter, etc.) was placed on the passenger seat the Passenger Presence Module may command the passenger air bag indicator to turn on and/or command the passenger seat belt indicator to turn on. Make sure there are no objects on the passenger seat and clear the DTCs. If this DTC resets then perform this diagnostic. If the DTC does not reset there is no further work needed on the passenger presence system.
3. If this DTC is set as either current or history it may have been caused by an aftermarket seat heater. The aftermarket seat heater may command the passenger air bag indicator to turn on and/or command the passenger seat belt indicator to turn on. Remove the aftermarket seat heater from the passenger seat and clear the DTCs. If this DTC resets then perform this diagnostic. If the DTC does not reset there is no further work needed on the passenger presence system.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. When removing connectors inspect for damage, corrosion or poor connection. Damage or corrosion in the following requires repair or replacement of the affected component/connector. Passenger Presence Module Inflatable Restraint Sensing and Diagnostic Module Passenger Presence Module harness connector Inflatable Restraint Sensing and Diagnostic Module wiring harness connector

1. Ignition ON, verify that DTC B0081 is the only DTC set in the Inflatable Restraint Sensing and Diagnostic Module or Passenger Presence Module. If any other DTCs are set, refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) .
2. Verify DTC B0081 00, or DTC B0081 3A is not set in the Inflatable Restraint Sensing and Diagnostic Module. If any of these DTCs set in the Inflatable Restraint Sensing and Diagnostic Module diagnose the following: Inflatable Restraint Sensing and Diagnostic Module DTC B0081 00: If DTC B0081 00 sets in the Inflatable Restraint Sensing and Diagnostic Module then the Passenger Presence Module will set DTC B0081 4B or DTC B0081 5A. Refer to step #3 and diagnose the Passenger Presence Module DTC's. By diagnosing these two DTC's in the Passenger Presence Module, DTC B0081 00 will be fixed in the Inflatable Restraint Sensing and Diagnostic Module. Inflatable Restraint Sensing and Diagnostic Module DTC B0081 3A: Either an incorrect replacement Passenger Presence Module or Inflatable Restraint Sensing and Diagnostic Module was placed in this vehicle. Check and make sure the part #'s are correct for each module. If both part #'s are correct clear this DTC and see if DTC B0081 3A resets as a current DTC. If DTC B0081 3A resets then replace the Passenger Presence Module. Clear DTCs again and check if DTC B0081 3A sets as current again. If DTC B0081 3A sets again then replace the Inflatable Restraint Sensing and Diagnostic Module.
3. Verify DTC B0081 4B, or DTC B0081 5A is not set in the Passenger Presence Module. If either of these DTCs set in the Passenger Presence Module diagnose the following: Passenger Presence Module DTC B0081 4B: If DTC B0081 4B sets in the Passenger Presence Module if the correct calibration was not learned by the Passenger Presence Module. Replace the Passenger Presence Module. Passenger Presence Module DTC B0081 5A: If DTC B0081 5A sets in the Passenger Presence Module check the connections at the Inflatable Restraint Sensing and Diagnostic Module and Passenger Presence Module. Clear the DTC's and check if DTC B0081 5A sets again in the Passenger Presence Module. If DTC B0081 5A sets again replace the Passenger Presence Module.

Perform the Diagnostic Repair Verification after completing the repair.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for passenger presence system and Inflatable Restraint Sensing and Diagnostic Module replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The impact sensors utilize a unidirectional 2-wire circuit. The impact sensors modulate 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 impact sensor. When the ignition is turned ON and input power from the SDM is first detected, the impact sensor 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 impact sensor continually communicates status messages to the SDM, which determines if a fault is present in the impact sensor circuit. When a fault is detected, the SDM may reset the impact sensor up to 2 times 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 V.

Any of the following conditions exist for 2.5 seconds

B0083 00, B0084 00, B0085 00, B0086 00, B0087 00, B0088 00

1. The impact sensor has been shorted to voltage, open, or shorted to ground.
2. The impact sensor current has been above 23 mA for longer than 5 milliseconds.
3. The SDM has not received a message from the impact sensor for more than 375 milliseconds.

B0083 0F, B0084 0F, B0085 0F, B0086 0F, B0087 0F, B0088 0F

The SDM has received erratic messages from the impact sensor.

B0083 39, B0084 39, B0085 39, B0086 39, B0087 39, B0088 39

1. The SDM has received a Not Ok (NOK) message from the impact sensor.
2. The SDM has not received a message.
3. The SDM has received invalid serial data from the impact sensor.

B0083 3A, B0084 3A, B0085 3A, B0086 3A, B0087 3A, B0088 3A

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

B0083 71, B0084 71, B0085 71, B0086 71, B0087 71, B0088 71

The SDM has received invalid serial data from the impact sensor.

1. The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
2. The SIR System is disabled and no deployments are allowed.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. Refer to SIR Service Precautions Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of the affected component/connector. Impact sensor SDM module Impact sensor wiring harness connector SDM wiring harness connector

Note. The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly. Replace any CPA that is damaged or missing. If the condition is intermittent or cannot be duplicated, disconnect the connectors and add dielectric grease / lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087). This procedure will correct the high resistance condition due to terminal fretting corrosion.

1. Verify that DTC B0083-B0088 symptom byte 39 or 71 is not set as current. If symptom byte 39 or 71 is set as current, replace the appropriate B59 front impact sensor or B63 side impact sensor.
2. Verify that the SDM calibrations match the VIN data, software part number, and calibration part number. If not the correct data or part number, program the SDM.
3. Verify the correct impact sensors have the correct part numbers, matching the label part numbers with the parts book. If the part numbers do not match, replace the incorrect B59 front impact sensor or B63 side impact sensor
4. Verify that DTC B0083-B0088 symptom byte 01, 02, 04, 05, or 0C is not set as current. If symptom byte 01, 02, 04, 05, or 0C is set as current, refer to Circuit/System Testing below.

1. Ignition OFF, disconnect the harness connector at the appropriate impact sensor.
2. Disconnect the harness connector at the SDM.
3. Ignition ON, test for less than 1 V between the following signal circuit and ground. Right front impact sensor terminal 1 Left front impact sensor terminal 1 Right front side impact sensor terminal B Left front side impact sensor terminal B Right rear side impact sensor terminal B Left rear side impact sensor terminal B If greater than the specified range, test the circuit for a short to voltage.
4. Ignition ON, test for less than 1 V between the low reference circuit and ground. Right front impact sensor terminal 2 Left front impact sensor terminal 2 Right front side impact sensor terminal A Left front side impact sensor terminal A Right rear side impact sensor terminal A Left rear side impact sensor terminal A If greater than the specified range, test the circuit for a short to voltage.
5. Test for infinite resistance between the signal circuit and ground. Right front impact sensor terminal 1 Left front impact sensor terminal 1 Right front side impact sensor terminal B Left front side impact sensor terminal B Right rear side impact sensor terminal B Left rear side impact sensor terminal B If less than the specified value, test the circuit for a short to ground.
6. Test for less than 1 ohms between the following signal circuit terminals. Right front impact sensor terminal 1 and SDM terminal 26 X2. Left front impact sensor terminal 1 and SDM terminal 23 X2. Right front side impact sensor terminal B and the SDM terminal 22 X2. Left front side impact sensor terminal B and the SDM terminal 19 X2. Right rear side impact sensor terminal B and the SDM terminal 30 X2. Left rear side impact sensor terminal B and the SDM terminal 27 X2. If greater than the specified range, test the circuit for an open/high resistance.
7. Test for less then 1 ohms between the following front end sensor low reference circuit terminals. Right front impact sensor terminal 2 and SDM terminal 25 X2. Left front impact sensor terminal 2 and SDM terminal 24 X2. Right front side impact sensor terminal A and the SDM terminal 21 X2. Left front side impact sensor terminal A and the SDM terminal 20 X2. Right rear side impact sensor terminal A and the SDM terminal 29 X2. Left rear side impact sensor terminal A and the SDM terminal 28 X2. If greater than the specified range, test the circuit for an open/high resistance.
8. If all circuits test normal, replace the appropriate impact sensor.
9. Reconnect all SIR components. Ignition ON, with a scan tool clear and check for DTCs. If the DTC returns and is current, replace the SDM.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Inflatable Restraint Front End Sensor Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Inflatable Restraint Side Impact Sensor Replacement (Crew Cab, Rear Door)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Inflatable Restraint Side Impact Sensor Replacement (Crew Cab/Extended Cab/Regular Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Inflatable Restraint Side Impact Sensor Replacement (Extended Cab, Rear Door)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
3. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
4. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for SDM replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The impact sensors are equipped on vehicles to supplement the supplemental inflatable restraint (SIR) system performance. The impact sensors are electronic and are not part of the deployment loops, but instead provide inputs to the inflatable restraint sensing and diagnostic module (SDM). The impact sensors can assist in determining the severity of some frontal and side collisions. The inflatable restraint sensing and diagnostic module uses the input from the impact sensors to assist in determining the severity of a collision further supporting air bag deployment. If the inflatable restraint sensing and diagnostic module determines a deployment is warranted, the inflatable restraint sensing and diagnostic module will cause current to flow through the deployment loops deploying the appropriate air bags. The center front impact sensor and side impact sensors utilize a bidirectional 2-wire circuit. The sensors modulate current on the interface to send identification, state of health, and deployment commands to the inflatable restraint sensing and diagnostic module. The inflatable restraint sensing and diagnostic module serves as a power source and a ground for the sensors. When the ignition is turned ON and input power from the inflatable restraint sensing and diagnostic module is first detected, the sensors respond by performing internal diagnostics and sending an identification to the inflatable restraint sensing and diagnostic module. The inflatable restraint sensing and diagnostic module considers the identification to be valid if the response time is less than 5 seconds. The sensors continually communicate status messages to the inflatable restraint sensing and diagnostic module, which determines if a fault is present in the sensor circuit. When a fault is detected, the inflatable restraint sensing and diagnostic module may reset the sensors up to 2 times by removing and reapplying power to it. If the fault is still present, the inflatable restraint sensing and diagnostic module will set a DTC.

Ignition voltage is between 9-16 V.

B0091 00

1. The front impact sensor has an open, been shorted to ground, or been shorted to voltage.
2. The center front impact sensor current is greater than 23 mA for greater than 5 milliseconds.

B0091 0F

The inflatable restraint sensing and diagnostic module has received erratic messages from the inflatable restraint front end sensor.

B0091 39

1. The inflatable restraint sensing and diagnostic module has received a Not OK (NOK) message from the inflatable restraint front end sensor.
2. The inflatable restraint sensing and diagnostic module has not received a message.

B0091 3A

1. The inflatable restraint sensing and diagnostic module has received identification message from the center front impact sensor which does not match the identification stored in the inflatable restraint sensing and diagnostic module memory.
2. The inflatable restraint sensing and diagnostic module has reset the center front impact sensor twice without detecting the correct identification message.

1. The inflatable restraint sensing and diagnostic module requests the instrument panel cluster to illuminate the AIR BAG indicator.
2. The SIR system is disabled and no deployments are allowed.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
4. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. Refer to SIR Service Precautions . Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of the affected component/connector. Front impact sensor Side impact sensor Inflatable restraint sensing and diagnostic module Front impact sensor wiring harness connector Side impact sensor wiring harness connector Inflatable restraint sensing and diagnostic module wiring harness connector The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly. Replace any CPA that is damaged or missing. If the condition is intermittent or cannot be duplicated, disconnect the connectors and add dielectric grease / lubricant (Nyogel 760G or equivalent, meeting GM specification 9986087). This procedure will correct the high resistance condition due to terminal fretting corrosion.

1. Verify DTC B0091 3A or B0091 39 is not set as current. If DTC B0091 3A or B0091 39 is set as current Replace the center front impact sensor. If DTC B0091 3A or B0091 39 is not set as current
2. Verify DTC B0091 00 or DTC B0091 0F is not set as current. If DTC DTC B0091 00 or DTC B0091 0F is set as current Refer to Circuit/System Testing below. If DTC DTC B0091 00 or DTC B0091 0F is not set as current
3. All OK.

1. Ignition OFF, disconnect the harness connector at the inflatable restraint front end sensor. It may take up to 2 minutes for all vehicle systems to power down.
2. Test for less than 10 ohms between the low reference circuit terminal 2 and ground. If 10 ohms or greater Ignition OFF, disconnect the X2 harness connector at the inflatable restraint sensing and diagnostic module. Test for less than 2 ohms in the low reference circuit end to end. If 2 ohms or greater, repair the open/high resistance in the circuit. If less than 2 ohms, replace the inflatable restraint sensing and diagnostic module. If less than 10 ohms
3. Ignition ON.
4. Test for less than 11 V between the signal circuit terminal 1 and ground. If 11 V or greater Ignition OFF, disconnect the X2 harness connector at the inflatable restraint sensing and diagnostic module, ignition ON. Test for less than 1 V between the signal circuit terminal 1 and ground. If 1 V or greater, repair the short to voltage on the circuit. If less than 1 V, replace the inflatable restraint sensing and diagnostic module. If less than 11 V
5. Ignition OFF.
6. Test for greater than 50k ohms between the signal circuit terminal 1 and ground. If 50k ohms or less Disconnect the X2 harness connector at the inflatable restraint sensing and diagnostic module. Test for infinite resistance between the signal circuit and ground. If less than infinite resistance, repair the short to ground on the circuit. If infinite resistance, replace the inflatable restraint sensing and diagnostic module. If greater than 50k ohms
7. Disconnect the X2 harness connector at the inflatable restraint sensing and diagnostic module.
8. Test for less than 2 ohms between the inflatable restraint front end sensor signal circuit terminal 1 and the inflatable restraint sensing and diagnostic module circuit terminal 23 X2. If 2 ohms or greater Repair the open/high resistance in the circuit. If less than 2 ohms
9. Ignition OFF, connect all harness connectors, press in the CPA (if equipped) until an audible and/or tactile click is heard.
10. Ignition ON, clear DTCs.
11. Verify the DTC does not set while operating the vehicle under the conditions for running the DTC. If the DTC sets Replace the inflatable restraint front end sensor. Verify the DTC does not set while operating the vehicle under the conditions for running the DTC. If the DTC sets, replace the inflatable restraint sensing and diagnostic module. If the DTC does not set All OK. If the DTC does not set
12. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

1. «Inflatable Restraint Front End Sensor Replacement (1500)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for inflatable restraint sensing and diagnostic module replacement, programming and setup

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using the diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The inflatable restraint I/P module disable switch enables or disables the passenger instrument panel air bag. When the ignition is turned ON, the inflatable restraint I/P module disable switch, based on the position of the switch ON or OFF, will be active to the inflatable restraint sensing and diagnostic module (SDM). The inflatable restraint sensing and diagnostic module will communicate to the passenger instrument panel air bag indicator to illuminate the appropriate the ON/OFF indicator as well as enable or disable the deployment of the passenger instrument panel air bag. If a malfunction is detected, a DTC will be stored.

Ignition 1 voltage is between 9-16 volts.

B0098 01, B0098 02, B0098 08

The inflatable restraint sensing and diagnostic module detects the I/P module disable switch control signal circuit active or inactive for 500 milliseconds.

The inflatable restraint sensing and diagnostic module requests the IPC to illuminate the AIRBAG indicator.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition OFF, disconnect the harness connector at the inflatable restraint I/P module disable switch.
2. Ignition ON.
3. Test for 6 V to 12 V between the I/P module disable switch signal control circuit terminal D and ground. If less than the specified range, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the inflatable restraint sensing and diagnostic module. If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the inflatable restraint sensing and diagnostic module.
4. Ignition OFF, test for less than 25 ohms between the I/P module disable switch ground circuit terminal A and ground. If greater than the specified range, test the ground circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the inflatable restraint sensing and diagnostic module.
5. If all circuits test normal, replace the inflatable restraint I/P module disable switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Instrument Panel Inflatable Restraint Module Switch Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
3. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for inflatable restraint sensing and diagnostic module replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The inflatable restraint sensing and diagnostic module (SDM) stores a primary data key, which is a 4-digit number, and a secondary data key, which is a portion of the vehicle identification number (VIN). 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 4-digit primary data key stored in the SDM does not match the 4 digits stored in the BCM.
2. The VIN stored in the BCM does not match that of the vehicle.

1. The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
2. The SDM disables all deployments.

1. The last 4-digit Primary Data Key in the SDM match the last 4 digits stored in the BCM.
2. The VIN that is stored in the SDM matches the VIN 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 was replaced without reprogramming the BCM with the new information.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
5. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information.

Note. When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected. SDM SDM wiring harness

1. Ignition ON, verify the scan tool Secondary Key Status displays Valid. If not the specified value, verify the scan tool Received VIN Digits 2-7 match the vehicle VIN, if the VIN does not match, reprogram the BCM. If the VIN matches, reprogram the SDM.
2. Ignition ON, verify the scan tool Primary Key Status displays Valid. If not the specified value, verify the scan tool SDM Primary Key matches the Received Primary Key, if the key does not match, perform the Setup SDM Primary Key in BCM procedure.
3. With a scan tool, verify DTC B1001 is not set as current. If DTC is set as current, replace the SDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The inflatable restraint sensing and diagnostic module (SDM) stores a 4-digit primary key for the inflatable restraint passenger presence system (PPS). The SDM sends the PPS module the primary key. If the PPS module determines that it is the wrong primary key, the PPS module will set DTC B1001 and send the SDM a vehicle mismatch message. The SDM then will set DTC B0081 and illuminate the SIR warning indicator. The PPS module does not use a secondary key.

Ignition voltage is between 9-16 volts.

The 4-digit primary key stored in the SDM does not match the 4-digit key stored in the PPS module.

1. The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
2. The passenger instrument panel air bag deployment is disabled.

The 4-digit Primary Key in the SDM and in the PPS module match.

This DTC is an indication that the PPS module was not set-up correctly, is not the correct part number or that the PPS module is defective.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
5. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Verify the correct PPS module part number has been installed If the wrong PPS module part number was installed, replace with the correct PPS module.
2. Verify that DTC B1001 is not set as current in the PPS module. If DTC is set as current, perform the PPS Preload procedure. Verify the SDM is sending the correct key. If DTC resets replace the PPS module.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The vehicle rollover sensor (ROS) monitors the vehicle speed signal (VSS) on the GMLAN serial data circuit. If the VSS is marked as invalid or is missing, the ROS will set a diagnostic trouble code (DTC).

Ignition voltage is between 9-16 volts.

If the VSS is marked as invalid or is missing.

1. The condition for setting the DTC no longer exists.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

DTC B1011 does not indicate a ROS system malfunction and will not cause any warning indicators to illuminate. Factors such as a long engine crank or a delay in serial data communications will cause B1011 to set.

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

SIR/SRS Wiring Repairs

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The Inflatable Restraint Sensing and Diagnostic Module (SDM) monitors the number of safety components installed on the vehicle. When the ignition is turned ON, the Inflatable Restraint Sensing and Diagnostic Module evaluates the number of safety components installed and compares it to the number of components the Inflatable Restraint Sensing and Diagnostic Module expects to see on the vehicle with its current calibration. If there is a mismatch between detected components and the components programmed with the Inflatable Restraint Sensing and Diagnostic Module calibration, DTC B1019 will set. The components (if equipped) that the Inflatable Restraint Sensing and Diagnostic Module will detect include inflatable restraint deployment loops, impact sensors, passenger presence system components, seat position sensors, disable switches, and seat belt switches.

Ignition voltage is between 9-16 V.

The setup for the Inflatable Restraint Sensing and Diagnostic Module has not been completed and the Inflatable Restraint Sensing and Diagnostic Module does not detect the passenger presence system (if equipped), the correct number of sensors, or deployment loops, that is expected with this calibration.

1. The Inflatable Restraint Sensing and Diagnostic Module requests the instrument cluster to illuminate the AIR BAG warning indicator.
2. The DTC must be cleared before running the setup Inflatable Restraint Sensing and Diagnostic Module.
3. Air bag indicator will continue to flash until Inflatable Restraint Sensing and Diagnostic Module setup procedure is complete.

1. The condition for setting the DTC is no longer present.
2. A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

The Inflatable Restraint Sensing and Diagnostic Module scan tool deployment loop, impact sensor, and passenger presence (if equipped) data will match what the Inflatable Restraint Sensing and Diagnostic Module has been programmed to expect to see on the vehicle. B1019 DTC will set if a deployment loop or impact sensor is added or removed from the system, or if the passenger presence is not detected.

DTC B1019 will set when an open/high resistance DTC sets for a deployment loop or impact sensor. This causes mismatch between the learned and actual components connected to the Inflatable Restraint Sensing and Diagnostic Module.

DTC B1019 can set with no other DTCs if an unused deployment loop or impact sensor circuit is shorted to ground. This causes a mismatch between the learned and actual components connected to the Inflatable Restraint Sensing and Diagnostic Module.

Schematic Reference

1. «Seat Belt Schematics»(/gmc/sierra-2500/2012-2012/remont/restraints-control-systems/#seat-belt-system)
2. «SIR Schematics»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

1. «Seat Belt System Description and Operation»(/gmc/sierra-2500/2012-2012/remont/restraints-control-systems/#seat-belt-system)
2. «SIR System Description and Operation»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
3. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

Note. DTC B1019 can set after the Inflatable Restraint Sensing and Diagnostic Module has been replaced and/or reprogrammed before the setup procedure is completed. The setup procedure cannot be completed if DTC B1019 is set as current or history. If a short or open is detected in a deployment circuit prior to the setup procedure being performed, the Inflatable Restraint Sensing and Diagnostic Module will set DTC B1019.

1. Ignition ON.
2. Verify no other Inflatable Restraint Sensing and Diagnostic Module DTCs are set. If other Inflatable Restraint Sensing and Diagnostic Module DTCs are set Diagnose those DTCs first. Refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) If no other Inflatable Restraint Sensing and Diagnostic Module DTCs are set
3. Verify the impact sensors identified in the scan tool data list match the number of actual impact sensors installed on the vehicle. If the number of impact sensors do not match Verify the correct Inflatable Restraint Sensing and Diagnostic Module calibration file is loaded in the Inflatable Restraint Sensing and Diagnostic Module. If the Inflatable Restraint Sensing and Diagnostic Module calibration file is correct and the vehicle contains an incorrect number of sensors, identify which sensors are missing to make the vehicle match the Inflatable Restraint Sensing and Diagnostic Module impact sensor calibration scan tool data list. If the calibration file is incorrect Reprogram the Inflatable Restraint Sensing and Diagnostic Module. Refer to «Inflatable Restraint Sensing and Diagnostic Module Programming and Setup»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__inflatable-restraint-sensing-and-diagnostic-module) If the number of impact sensors match
4. Verify the enabled deployment loops identified in the scan tool data list match the deployment loops installed on the vehicle. If the number of enabled deployment loops do not match Verify the correct Inflatable Restraint Sensing and Diagnostic Module calibration file is loaded in the Inflatable Restraint Sensing and Diagnostic Module. If the Inflatable Restraint Sensing and Diagnostic Module calibration file is correct and the vehicle contains an incorrect number of loops, identify which deployment loops are missing to make the vehicle match the Inflatable Restraint Sensing and Diagnostic Module impact sensor calibration scan tool data list. If the calibration file is incorrect Reprogram the Inflatable Restraint Sensing and Diagnostic Module. Refer to «Inflatable Restraint Sensing and Diagnostic Module Programming and Setup»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__inflatable-restraint-sensing-and-diagnostic-module) If the number of enabled deployment loops match
5. Verify a passenger presence system is equipped on the vehicle. If a passenger presence system is not equipped on the vehicle Replace the K36 Inflatable Restraint Sensing and Diagnostic Module. If a passenger presence system is equipped on the vehicle
6. Verify the Passenger Presence Enable Status parameter identified in the scan tool data list is enabled. If the Passenger Presence Enable Status parameter is not Enabled Refer to «Inflatable Restraint Sensing and Diagnostic Module Programming and Setup»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__inflatable-restraint-sensing-and-diagnostic-module) If the passenger presence parameter is Enabled
7. Verify the Passenger Presence Learn Status parameter identified in the scan tool data list is learned. If the Passenger Presence Learn Status parameter is not Learned Verify the scan tool can communicate with the passenger presence system. If the scan tool will not communicate with the passenger presence system, refer to «Scan Tool Does Not Communicate with Low Speed GMLAN Device»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#data-communications-system) If the scan tool communicates Ignition OFF, disconnect the scan tool, wait two minutes. Ignition ON, verify DTC B1019 is not set as current. If the DTC is set as current, refer to «Inflatable Restraint Sensing and Diagnostic Module Programming and Setup»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__inflatable-restraint-sensing-and-diagnostic-module) If the DTC is not set as current All OK. If the passenger presence learn status is Learned
8. Replace the K36 Inflatable Restraint Sensing and Diagnostic Module.

Perform the Diagnostic Repair Verification after completing the repair.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for Inflatable Restraint Sensing and Diagnostic Module replacement, programming and setup

Symptoms - SIR

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the SIR system. Refer to «Checking Aftermarket Accessories»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__checking-aftermarket-accessories) .
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 .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

Air Bag Indicator Circuit Malfunction (Passenger) , Air Bag Indicator Circuit Malfunction (Driver)

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

When the ignition is turned ON, the instrument panel cluster (IPC) flashes the air bag indicator for a bulb check. The inflatable restraint sensing and diagnostic module (SDM) performs diagnostic tests on the SIR system during the bulb check. If any malfunction exists the SDM will request the IPC to illuminate the air bag indicator steady, via serial data. If a preexisting malfunction exists, the air bag indicator will illuminate steady immediately after the ignition is turned ON. If the ignition 1 voltage is outside of the normal operating voltage range 9-16 volts, the SDM will command the IPC to illuminate the air bag indicator with no DTCs present, then disables all deployment loops.

A DTC B1370 may set if the ignition 1 circuit is outside the 9-16 volts range.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, verify the SDM Battery Voltage Signal parameter is 9-16 volts. If not the specified range, refer to «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) .
2. Ignition OFF, monitor the IPC, ignition ON. The SIR warning indicator should flash then turn OFF. If the SIR warning indicator continually flashes, program the SDM. If the SIR warning indicator remains on steady, test for DTCs and refer to «Diagnostic Trouble Code (DTC) List - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-trouble-code-dtc-list) . If no DTC is current, proceed to the next step.
3. Perform the Display Test in Instrument Panel Cluster/Special Functions. The Air Bag indicator should turn ON and OFF as commanded. If the air bag indicator does not illuminate as expected, replace the IPC.
4. If all circuits test normal, replace the SDM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for IPC and SDM replacement, setup, and programming

1. Perform the «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) prior to using this diagnostic procedure.
2. Review «Strategy Based Diagnosis»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__strategy-based-diagnosis) for an overview of the diagnostic approach.
3. «Diagnostic Procedure Instructions»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures__diagnostic-procedure-instructions) provides an overview of each diagnostic category.

The PASSENGER AIR BAG ON/OFF indicators are used to notify the driver when the Passenger Presence System (PPS) has enabled or disabled the passenger instrument panel air bag. When the ignition is turned ON, the passenger presence module will commands both PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. The passenger presence 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 passenger presence module will turn the PASSENGER AIR BAG indicator ON or OFF, depending on the status of the PPS. If a malfunction is detected, the passenger presence module will store a DTC, default the PPS to the OFF state, and communicate with the inflatable restraint sensing and diagnostic module (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 malfunction.

Schematic Reference

SIR Schematics

Connector End View Reference

WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX

Description and Operation

SIR System Description and Operation

Electrical Information Reference

1. «Circuit Testing»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__circuit-testing)
2. «Connector Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__connector-repairs)
3. «Testing for Intermittent Conditions and Poor Connections»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__testing-for-intermittent-conditions-and-poor)
4. «Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__wiring-repairs)
5. «SIR/SRS Wiring Repairs»(/gmc/sierra-2500/2012-2012/remont/ignition-switchsteering-lock/#wiring-systems-and-power-management-diagnostic-information-and-procedures__sirsrs-wiring-repairs)

Scan Tool Reference

Control Module References for scan tool information

1. Ignition OFF, disconnect the harness connector at the inflatable restraint passenger air bag On/Off indicator.
2. Ignition OFF, test for less then 1 ohm between the ground circuit terminal 2 and ground. If greater then the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify a test lamp illuminates between the ignition circuit terminal 4 and ground. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test or replace the inflatable restraint passenger air bag On/Off indicator.
4. Connect a test lamp between the control circuit terminal 3 and the ignition circuit terminal 4. With the passenger seat unoccupied, then occupied the test lamp should switch states within 5 seconds. If the test lamp is always on, test the control circuit for a short to ground. If all circuits test normal replace the IPC. If the test lamp is always off, test the control circuit for a short to voltage or an open/high resistance. If all circuits test normal replace the IPC.
5. Connect a test lamp between the control circuit terminal 1 and the ignition circuit terminal 4. With the passenger seat unoccupied, then occupied the test lamp should switch states within 5 seconds. If the test lamp is always on, test the control circuit for a short to ground. If all circuits test normal replace the IPC. If the test lamp is always off, test the control circuit for a short to voltage or an open/high resistance. If all circuits test normal replace the IPC.
6. If all circuits test normal, replace the inflatable restraint passenger air bag on/off indicator.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

1. «Inflatable Restraint Instrument Panel Module Indicator Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)
2. «Control Module References»(/gmc/sierra-2500/2012-2012/remont/communication-devices/#programming-and-setup-all-systems__control-module-references) for IPC and SDM replacement, setup, and programming

SIR Disabling and Enabling

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

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

SIR Service Precautions

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

General Service Instructions

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

1. Do not expose air bags to temperatures above 65°C (149°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 92 cm (3 feet) or greater

1. Inflatable restraint sensing and diagnostic module (SDM)
2. Any air bag
3. Driver steering wheel air bag coil
4. Any impact sensor
5. Seat belt anchor and/or retractor pretensioners
6. Passenger presence module and/or occupant sensor

Disabling Procedure - Air Bag Fuse

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Place the ignition in the OFF position.
3. Locate and remove the fuse(s) supplying power to the SDM. Refer to «SIR Schematics»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , or «Electrical Center Identification Views»(/gmc/sierra-2500/2012-2012/remont/electrical-component-locations/#wiring-systems-and-power-management-component-locator-electrical-center-identification-views) .
4. Wait 1 minute before working on the system.

Enabling Procedure - Air Bag Fuse

1. Place the ignition in the OFF position.
2. Install the fuse(s) supplying power to the SDM. Refer to «SIR Schematics»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , or «Electrical Center Identification Views»(/gmc/sierra-2500/2012-2012/remont/electrical-component-locations/#wiring-systems-and-power-management-component-locator-electrical-center-identification-views) .
3. Turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
4. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) .

Disabling Procedure - Negative Battery Cable

1. Turn the steering wheel so that the vehicles wheels are pointing straight ahead.
2. Place the ignition in the OFF position.
3. Disconnect the negative battery cable from the battery. Refer to «Battery Negative Cable Disconnection and Connection (TP2)»(/gmc/sierra-2500/2012-2012/remont/charging-system/#battery-charging-system-and-starting-system) , «Battery Negative Cable Disconnection and Connection (Single Battery)»(/gmc/sierra-2500/2012-2012/remont/charging-system/#battery-charging-system-and-starting-system) .
4. Wait 1 minute before working on system.

Enabling Procedure - Negative Battery Cable

1. Place the ignition in the OFF position.
2. Connect the negative battery cable to the battery. Refer to «Battery Negative Cable Disconnection and Connection (TP2)»(/gmc/sierra-2500/2012-2012/remont/charging-system/#battery-charging-system-and-starting-system) , «Battery Negative Cable Disconnection and Connection (Single Battery)»(/gmc/sierra-2500/2012-2012/remont/charging-system/#battery-charging-system-and-starting-system) .
3. Turn the ignition switch to the ON position. The AIR BAG indicator will flash then turn OFF.
4. Perform the Diagnostic System Check - Vehicle if the AIR BAG warning indicator does not operate as described. Refer to «Diagnostic System Check - Vehicle»(/gmc/sierra-2500/2012-2012/remont/oem-general-information/#vehicle-diagnostic-information-diagnostic-information-and-procedures) .

General Service Instructions

Note. The inflatable restraint sensing and diagnostic module (SDM) maintains a reserved energy supply. The reserved energy supply provides deployment power for the SIR air bags. Deployment power may be available for up to 60 seconds after disconnecting the vehicle power. Disabling the SIR system prevents deployment of the SIR air bags from the reserved energy supply.

Note. 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 air bags to temperatures above 65°C (149°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

Note. Discard any of the following components if it has been dropped from a height of 92 cm (3 ft) or greater

1. SDM
2. Passenger instrument panel air bag
3. Driver steering wheel air bag
4. Driver steering wheel air bag coil
5. Roof rail air bags
6. Front and /or side impact sensors
7. Seat belt achor and/or retractor pretensioners
8. Front seat side air bag

Scheme 7

Inflatable Restraint Front End Sensor Replacement (1500)

Scheme 8

Inflatable Restraint Side Impact Sensor Replacement (Crew Cab/Extended Cab/Regular Cab)

Scheme 9

Inflatable Restraint Side Impact Sensor Replacement (Extended Cab, Rear Door)

Scheme 10

Inflatable Restraint Side Impact Sensor Replacement (Crew Cab, Rear Door)

Scheme 11

Airbag Sensing and Diagnostic Module Replacement

Scheme 12

Steering Wheel Inflatable Restraint Module Replacement

Steering Wheel Airbag Coil Replacement

Special Tools

J 42640 Steering Column Anti-Rotation Pin

Removal Procedure

1. Verify the following before removing the inflatable restraint steering wheel module coil: The wheels on the vehicle are straight ahead. That J 42640 steering column anti-rotation pin is installed or the ignition and start switch is in the LOCK position.
2. Remove the steering wheel. Refer to «Steering Wheel Replacement»(/gmc/sierra-2500/2012-2012/remont/steering-column-switches/#steering-wheel-and-steering-column) .
3. Remove the steering column shroud. Refer to «Steering Column Shroud Replacement»(/gmc/sierra-2500/2012-2012/remont/steering-column-switches/#steering-wheel-and-steering-column) .
4. Disconnect any electrical connectors as needed.
5. Remove the inflatable restraint steering wheel module coil retaining ring (2) and discard it. DO NOT reuse the ring.
6. Remove the inflatable restraint steering wheel module coil (1) from the steering shaft.
7. If replacing, discard the old inflatable restraint steering wheel module coil.

Installation Procedure

1. If reusing the existing inflatable restraint steering wheel module coil it MUST be centered. Refer to «Inflatable Restraint Steering Wheel Module Coil Centering»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system__inflatable-restraint-steering-wheel-module-coil) .
2. Align the inflatable restraint steering wheel module coil (1) with the horn tower on the turn signal switch cancel cam (2).
3. Slide the inflatable restraint steering wheel module coil (4) onto the steering shaft (2).
4. Firmly seat the new inflatable restraint steering wheel module coil retaining ring (3) into the appropriate groove on the steering shaft (2).
5. Remove and discard the centering tab from the new inflatable restraint steering wheel module coil (4).
6. Connect any electrical connectors as needed.
7. Install the steering column shroud. Refer to «Steering Column Shroud Replacement»(/gmc/sierra-2500/2012-2012/remont/steering-column-switches/#steering-wheel-and-steering-column) .
8. Install the steering wheel. Refer to «Steering Wheel Replacement»(/gmc/sierra-2500/2012-2012/remont/steering-column-switches/#steering-wheel-and-steering-column) .
9. Remove J 42640 steering column anti-rotation pin.

Inflatable Restraint Steering Wheel Module Coil Centering

1. Verify the following conditions before centering the SIR coil: The front wheels of the vehicle are in the straight ahead position. The block tooth (1) of the steering shaft assembly is in the 12 o'clock position. The ignition switch is in the LOCK position.
2. Remove the wire harness strap or straps where necessary.
3. Hold the SIR coil and look at the side with the letters POM (1).
4. Rotate the coil hub clockwise until the coil ribbon stops.
5. From the clockwise stop, rotate the coil hub slowly counterclockwise approximately 3.3 turns. Place the uplead connector (2) in the 12 o'clock position. Ensure the flat wire cable loop appears in the centering window (4). This is the CENTER position.
6. If you have the orange lock pin (3), use the lock pin to lock the SIR coil in the center position. If you do not have the orange lock pin, hold the SIR coil in the center position.
7. Align the SIR coil with the horn tower and slide the SIR coil onto the steering shaft assembly.
8. If a double wire harness strap is installed onto the wire harness assembly and the column, you must route the wires up against the steering column. One wire harness strap will surround one lead from the coil to the steering column. The other wire harness strap will surround all other leads to the steering column.

Scheme 13

Instrument Panel Inflatable Restraint Module Replacement (With SLT)

Scheme 14

Instrument Panel Inflatable Restraint Module Replacement (Without SLT)

Scheme 15

Inflatable Restraint Seat Position Sensor Replacement

Scheme 16

Inflatable Restraint Passenger Presence System Replacement - Front (without HP2)

Scheme 17

Inflatable Restraint Passenger Presence System Replacement - Front (with HP2)

Scheme 18

Driver or Passenger Seat Side Inflatable Restraint Module Replacement

Scheme 19

Inflatable Restraint Instrument Panel Module Indicator Replacement

Scheme 20

Instrument Panel Inflatable Restraint Module Switch Replacement

Scheme 21

Roof Side Rail Inflatable Restraint Module Replacement (Extended Cab)

Scheme 22

Roof Side Rail Inflatable Restraint Module Replacement (Regular Cab)

Scheme 23

Roof Side Rail Inflatable Restraint Module Replacement (Crew Cab)

Scheme 24

Seat Belt Retractor Pretensioner Replacement - Front (Regular Cab)

Scheme 25

Seat Belt Retractor Pretensioner Replacement - Front (Extended Cab)

Scheme 26

Seat Belt Retractor Pretensioner Replacement - Front (Crew Cab)

Accident With or Without Air Bag Deployment - Component Inspections

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

Note. Hybrid Vehicles Only - Perform an inspection of the high voltage system for damage. Refer to High Voltage System Inspection .

1. The steering column-Inspect the steering column for bending, twisting, buckling or any type of damage.
2. The instrument panel knee bolsters and mounting points-Inspect the knee bolsters for bending, twisting, buckling, or any other type of damage.
3. The instrument panel brackets, braces, etc.-Inspect for bending, twisting, buckling, or any other type of damage.
4. The seat belts-Perform the seat belt operational and functional checks. Refer to «Repairs and Inspections Required After a Collision»(/gmc/sierra-2500/2012-2012/remont/restraints-control-systems/#seat-belt-system__repairs-and-inspections-required-after-a) .
5. The instrument panel cross car beam-Inspect for bending, twisting, buckling, or any other type of damage.
6. The instrument panel mounting points and brackets-Inspect for bending, twisting, buckling, or any other type of damage.
7. The seats and seat mounting points-Inspect for bending, twisting, buckling, or any other type of damage.
8. The roof and headliner mounting points.
9. The brake pedal --Inspect the brake pedal for bending, twisting, buckling or any type of damage.

Accident With Frontal Air Bag Deployment - Component Replacement and Inspections

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

1. Driver steering wheel air bag
2. Passenger instrument panel air bag, if deployed
3. Inflatable restraint sensing and diagnostic module (SDM), if SDM has DTC B0052 56
4. Front and/or side impact sensors
5. Driver/Passenger seat side air bag, if deployed
6. Seat back cover if side seat air bag is deployed
7. Driver/Passenger seat belt anchor and/or retractor pretensioners

Perform additional inspections on the following components.

1. Steering wheel air bag 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 passenger instrument panel air bag, steering wheel air bag, SDM, seat side air bag (if deployed) and seat belt anchor and/or retractor pretensioners-Inspect for any damage and repair or replace each component as needed.

Accident With Side Seat Air Bag Deployment - Component Replacement and Inspections

After a collision involving driver/passenger side seat air bag deployment, replace the following components.

1. Left/right side impact sensors on the side of the impact.
2. Left/right roof rail air bag on the side of the impact.
3. Inflatable restraint sensing and diagnostic module (SDM), if SDM has DTC B0052 56.
4. Inflatable restraint seat belt anchor and/or retractor pretensioner.
5. Driver or passenger seat back cushion cover replacement.

Perform additional inspections on the following components.

1. Mounting points or mounting hardware for the side impact sensors, and driver/passenger side seat air bags on the side of impact-Inspect for any damage and repair or replace each component as needed.
2. Mounting points, mounting hardware, headliner and trim pieces for the left/right roof rail air bag 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 anchor and/or retractor pretensioners-Inspect for any damage and repair or replace each component as needed.
4. The seat cushion frame
5. The seat recliner and cover, if equipped
6. The seat adjuster
7. The seat back frame
8. Door trim assembly
9. Impacted seat cushion side covers and switches

Impact Sensor Replacement Guidelines

The impact sensor replacement policy requires replacing sensors in the area of the accident damage. The area of accident damage is defined as the portion of the vehicle which is crushed, bent, or damaged due to a collision. An example of this would be a moderate collision where the front of the vehicle impacts a object. If the vehicle has an impact sensor mounted forward of the radiator, it must be replaced.

1. Replace the impact sensor whether or not the air bags have deployed.
2. Replace the impact sensor even if it appears to be undamaged.

Impact sensor damage which is not visible, such as slight bending of the mounting bracket or cuts in the wire insulation, can cause improper operation of the SIR system. Do not try to determine whether the impact sensor is undamaged, replace the impact sensor. Also, if you follow a diagnostic trouble code (DTC) procedure and a malfunctioning impact sensor is indicated, replace the impact sensor.

Live and Undeployed Inflator Module

Scheme 27

Take special care when handling or storing an 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 2 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 dual stage module is required, both deployment loops must be energized to deploy the air bag.

Scrapping Procedure

During the course of a vehicles useful life, certain situations may arise which will require the disposal of a live and undeployed inflator module. Do NOT dispose a live and undeployed inflator module through normal disposal channels until the inflator module has been deployed.

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, GM-1241, related to the SIR system and is subject to a preliminary investigation-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

You can deploy the inflator module either 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. Situations that require deployment outside of the vehicle include the following

1. Using the SIR diagnostics, you determine that the inflator module is malfunctioning.
2. The inflator module is cosmetically damaged, scratched, or ripped.
3. The inflator module pigtail 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.

Special Tools

1. J 38826 SIR Deployment Harness
2. J 39401-B SIR Deployment Fixture
3. An appropriate pigtail adapter

1. Turn OFF the ignition.
2. Remove the ignition key.
3. Put on safety glasses.
4. Remove the inflator module. If you are removing the steering wheel module, refer to «Steering Wheel Inflatable Restraint Module Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) . If you are removing the I/P module, refer to «Instrument Panel Inflatable Restraint Module Replacement (Without SLT)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Instrument Panel Inflatable Restraint Module Replacement (With SLT)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) . If you are removing a roof rail module, refer to «Roof Side Rail Inflatable Restraint Module Replacement (Regular Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Roof Side Rail Inflatable Restraint Module Replacement (Extended Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Roof Side Rail Inflatable Restraint Module Replacement (Crew Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) .
5. Place the inflator module on a work bench, with the vinyl trim cover facing up and away from the surface.
6. Clear a space on the ground about 1.85 m (6 ft) in diameter for deployment of the inflator module or deployment fixture. If possible, use a paved, outdoor location free of activity. Otherwise, use a space free of activity on the shop floor. Ensure you have sufficient ventilation.
7. Clear the area of loose or flammable objects.
8. If you are deploying a steering wheel inflator module, place the inflator module in the center of the space.
9. When deploying an I/P inflator module, perform the following instructions: Place the J 39401-B SIR deployment fixture in the center of the cleared area. 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).
10. When deploying a roof rail module, perform the following instructions: Place the J 39401-B SIR deployment fixture (3) in the center of the cleared area. Fill the deployment fixture with water or sand to provide sufficient stabilization of fixture during deployment. Adjust and secure the fixture arms (4) to the deployment fixture (3), using the proper nuts and bolts. Attach the roof rail module in the deployment fixture and securely tighten all fasteners.
11. Inspect the SIR deployment harness and the appropriate pigtail adapter (2) for damage. Replace as needed.
12. Short the 2 SIR deployment harness leads (1) 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 the full length from the deployment fixture or area.
15. Connect the inflator module (1) to the adapter (2) on the SIR deployment harness (3).
16. Clear the area of people.
17. Separate the 2 banana plugs on the SIR deployment harness that were shorted together earlier in the procedure.
18. Place a 12-volt minimum/2-amp 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. Deployment of the inflator module will occur when contact is made.
20. Disconnect the SIR deployment harness from the power source after the inflator module deploys.
21. If the inflator module did not deploy, disconnect the adapter and discontinue the procedure and contact the Technical Assistance Group. If deployment was successful, proceed to the following steps.
22. Seat one banana plug into the other in order to short the deployment harness leads.
23. Put on a pair of shop gloves.
24. Disconnect the pigtail adapter from the inflator module as soon as possible.
25. Inspect the pigtail adapter and the SIR deployment harness. Replace as needed.
26. Dispose of the deployed inflator module through normal refuse channels.
27. Wash your 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 all useful life.
2. Irreparable damage occurred to the vehicle in a non-deployment type accident.
3. Irreparable damage occurred 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. Lower the driver and passenger windows.
2. Turn the ignition switch to the OFF position and remove the ignition key.
3. Check that all inflator modules which will be deployed are mounted securely. Driver inflator module is secured to the steering wheel. Passenger inflator module is secured to the instrument panel. Left roof rail inflator module is secured to the left roof rail. Right roof rail inflator module is secured to the right roof rail.
4. Put on safety glasses.
5. Remove all loose objects from the front seats.
6. Disconnect the steering wheel module yellow connector (1) from vehicle harness yellow connector (2).
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 gauge) 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.
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 the 2 connector wire leads from the high circuits from both stages of the steering wheel module, to one set of deployment wires. Refer to «Component Connector End Views»(/gmc/sierra-2500/2012-2012/remont/body-electrical/#wiring-systems-and-power-management-component-connector-end-views-rear-fender-clearance-lamp-lr-ro5-to-yaw-sensor) 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 the deployment harness using electrical tape.
16. Twist together the 2 connector wire leads from the low circuits from both stages of the steering wheel module, to one set of deployment wires. Refer to «Component Connector End Views»(/gmc/sierra-2500/2012-2012/remont/body-electrical/#wiring-systems-and-power-management-component-connector-end-views-rear-fender-clearance-lamp-lr-ro5-to-yaw-sensor) 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 the deployment harness using electrical tape.
20. Connect the deployment harness to the connector on the steering wheel module.
21. Route the deployment harness out of the driver side of the vehicle.
22. Disconnect the yellow left roof rail harness connector from the vehicle harness connector.
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 gauge) or thicker multi-strand wire. These wires will be used to fabricate the roof rail air bag deployment harness.
26. Strip 13 mm (0.5 in) of insulation from both ends of the wires.
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 yellow connector of the roof rail module.
33. Route the deployment harness out of the driver side of the vehicle.
34. Disconnect the I/P module yellow harness connector (1) from the vehicle harness connector (2).
35. Cut the yellow 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 gauge) or thicker multi-strand wire. These wires will be used to fabricate the passenger deployment harness.
38. Strip 13 mm (0.5 in) of insulation from both ends of the wires.
39. Twist together one end from each of the wires in order to short the wires.
40. Twist together the 2 connector wire leads from the high circuits from both stages of the I/P module to one set of deployment wires. Refer to «Component Connector End Views»(/gmc/sierra-2500/2012-2012/remont/body-electrical/#wiring-systems-and-power-management-component-connector-end-views-rear-fender-clearance-lamp-lr-ro5-to-yaw-sensor) in order to determine the correct circuits.
41. Inspect that the 3-wire connection is secure.
42. Bend flat the twisted connection.
43. Secure and insulate the 3-wire connection to the deployment harness using electrical tape.
44. Twist together the 2 connector wire leads from the low circuits from both stages of the I/P module to one set of deployment wires. Refer to «Component Connector End Views»(/gmc/sierra-2500/2012-2012/remont/body-electrical/#wiring-systems-and-power-management-component-connector-end-views-rear-fender-clearance-lamp-lr-ro5-to-yaw-sensor) in order to determine the correct circuits.
45. Inspect that the 3-wire connection is secure.
46. Bend flat the twisted connection.
47. Secure and insulate the 3-wire connection to the deployment harness using electrical tape.
48. Connect the deployment harness to the I/P module in-line connector.
49. Route the deployment harness out of the passenger side of the vehicle.
50. Disconnect the yellow harness connector to the right roof rail air bag from the vehicle harness connector.
51. Cut the harness connector out of the vehicle, leaving at least 16 cm (6 in) of wire at the connector.
52. Strip 13 mm (0.5 in) of insulation from each of the connector wire leads.
53. Cut two 6.1 m (20 ft) deployment wires from a 0.8 mm (18 gauge) or thicker multi-strand wire. These wires will be used to fabricate the roof rail module deployment harness.
54. Strip 13 mm (0.5 in) of insulation from both ends of the wires.
55. Twist together one end from each of the wires in order to short the wires.
56. Twist together one connector wire lead to one deployment wire.
57. Bend flat the twisted connection.
58. Secure and insulate the connection using electrical tape.
59. Twist together, bend, and tape the remaining connector wire lead to the remaining deployment wire.
60. Connect the deployment harness to the roof rail module yellow connector.
61. Route the deployment harness out of the passenger side of the vehicle.
62. Completely cover the windshield and the front door window openings with a drop cloth.
63. Stretch to the full length all of the deployment harness wires on the right side of the vehicle.
64. Deploy each deployment loop one at a time.
65. Place a power source, 12 V minimum/2 A minimum, such as a vehicle battery, near the shorted end of the harnesses.
66. Separate one set of wires and touch the wire ends to the power source in order to deploy the selected inflator module.
67. Disconnect the deployment harness from the power source and twist the wire ends together.
68. Continue the same process with the remaining deployment harnesses.
69. Stretch to the full length all of the deployment harness wires on the left side of the vehicle.
70. Deploy each deployment loop one at a time.
71. Place a power source, 12 V minimum/2 A minimum, such as a vehicle battery, near the shorted end of the harnesses.
72. Separate one set of wires and touch the wires ends to the power source in order to deploy the selected inflator modules.
73. Disconnect the deployment harness from the power source and twist the wire ends together.
74. Continue the same process with the remaining deployment harnesses.
75. Remove the drop cloth from the vehicle.
76. Disconnect all harnesses from the vehicle.
77. Discard the harnesses.
78. Scrap the vehicle in the same manner as a non-SIR equipped vehicle.
79. If one or all of the inflator modules did not deploy, perform the following steps to remove the undeployed modules from the vehicle: «Steering Wheel Inflatable Restraint Module Replacement»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) «Instrument Panel Inflatable Restraint Module Replacement (Without SLT)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Instrument Panel Inflatable Restraint Module Replacement (With SLT)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) «Roof Side Rail Inflatable Restraint Module Replacement (Regular Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Roof Side Rail Inflatable Restraint Module Replacement (Extended Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system) , «Roof Side Rail Inflatable Restraint Module Replacement (Crew Cab)»(/gmc/sierra-2500/2012-2012/remont/airbag/#supplemental-inflatable-restraint-system)

During the course of a vehicles 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.

Note. Some countries, states or localities may not allow service deployment of air bags without special permission or training. Local laws regarding deploying and scrapping of air bags/devices with pyrotechnics must be followed.

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 Inflatable Restraint 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 (if equipped) 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.

Special Tools

1. EL-39401-B SIR Deployment Fixture
2. EL-38826 SIR Deployment Harness

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.
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 the EL-39401-B SIR deployment fixture in the center of the cleared area.
9. Fill the fixture plastic reservoir with water or sand.
10. Mount the pretensioner (1) in the SIR deployment fixture (3) with the open end facing up using the following mounting method. Adjust and secure the EL-39401-B arms (4) to the deployment fixture (3). 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 EL-38826 SIR deployment harness and the appropriate pigtail adapter for damage. 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 (i.e., 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 one 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 hands with a mild soap.

SIR System Overview

The supplemental inflatable restraint (SIR) system supplements the protection offered by the seat belts. The SIR system contains an inflatable restraint sensing and diagnostic module (SDM), air bags, seat belt pretensioner (retractor), and impact sensors. The SDM determines the severity of a collision with the assistance of impact sensors located at strategic points on the vehicle. When the SDM detects a collision, the SDM will process the information provided by the sensors to further support air bag or pretensioner deployment. The SDM will deploy the air bags and pretensioners if it detects a collision of sufficient force. If the force of the impact is not sufficient to warrant air bag deployment, the SDM may still deploy the seat belt pretensioners. The SDM contains a sensing device that converts vehicle velocity changes to an electrical signal. The SDM compares these signals to values stored in memory. If the signals exceed a stored value, the SDM will determine the severity of the impact and either cause current to flow through the frontal deployment loops deploying the frontal air bags and pretensioners, or it will deploy the pretensioners only. The SDM continuously monitors the deployment loops for malfunctions and illuminates the SIR system AIR BAG indicator if a fault is detected. 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 illuminating the SIR system AIR BAG indicator. The steering column and knee bolsters 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.

SIR System AIR BAG Indicator

The SIR system AIR BAG indicator, located in the instrument cluster, is used to notify the driver of SIR system malfunctions and to verify that the inflatable restraint sensing and diagnostic module (SDM) is communicating with the instrument cluster. When the ignition is turned ON, the SDM is supplied with ignition positive voltage. The instrument cluster will momentarily turn on the SIR system AIR BAG indicator. While the indicator is on, the SDM conducts tests on all SIR system components and circuits. If no malfunctions are detected the SDM will communicate with the instrument cluster through the serial data circuit and command the SIR system 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 instrument cluster to illuminate the SIR system AIR BAG indicator via serial data. 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 SIR system AIR BAG indicator will remain ON until the malfunction has been repaired.

Inflatable Restraint Sensing and Diagnostic Module (SDM)

The inflatable restraint sensing and diagnostic module (SDM) is a microprocessor and the control center for the supplemental inflatable restraint (SIR) system. The SDM contains internal sensors along with external impact sensors, mounted at strategic locations on the vehicle. In the event of a collision, the SDM compares the signals from the internal and external impact 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 illuminates the SIR system AIR BAG indicator located in the instrument cluster. 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 request the instrument cluster to illuminate the SIR system AIR BAG indicator, notifying the driver that a malfunction exists. In the event that ignition positive voltage is lost during a collision, the SDM maintains a 23-volt loop reserve for deployment of the air bags. It is important when disabling the SIR system for servicing or rescue operations to allow the 23-volt loop reserve to dissipate, which could take up to 1 minute.

Air Bags

This vehicle contains 6 air bags. The 6 air bags are located in the steering wheel (dual air bags), instrument panel (passenger side) (dual air bags), driver side (seat), passenger side (seat), left roof rail, right roof rail. To view the locations of the air bags refer to SIR Identification Views . Air bags contain a housing, inflatable air bag, two initiating devices (if dual air bags), canister of gas generating material and, in some cases, stored compressed gas. The deployment loops supply current to deploy the air bags. The steering wheel and passenger instrument panel air bags have two stages of deployment, which varies the amount of restraint to the occupant according to the collision severity. For moderate frontal collisions the air bags deploy at less than full deployment which consists of stage 1 of the air bag. For more severe frontal collisions a full deployment is initiated which consists of stage 1 and stage 2 of the air bag. The current passing through the air bags ignite 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. A shorting bar (if equipped) is located in the connector.

Seat Position Sensors

The seat position sensor (SPS) is used to determine the proximity of a front driver position with respect to the frontal air bag. The state of the SPS allows the SDM to disable stage 2 of the frontal air bag for a front seat that is forward of a forward/rearward point in seat track travel. The SPS is a hall effect sensor that is mounted on the outboard seat track of the driver seat. The seat track includes a metal bracket that shunts the SPS magnetic circuit creating two states of seat position. The shunted state represents a rarward seat position. The non-shunted state represents a forward position. The SPS provides 2 current ranges, one range for the shunted state and a second range for a non-shunted state. These 2 states are inputs to the SDM. State 1 (shunted) being the rearward threshold and state 2 (non-shunted) being the forward threshold. When the SDM receives input from a SPS that state 1 threshold is reached (seat is rearward) the SDM will not disable stage 2 deployment, if required by the deployment sensors. When state 2 threshold is reached (seat is forward) the SDM will disable stage 2 deployment on the side the seat is forward.

Passenger Seat Belt Tension Sensor

The seat belt tension sensor is used to enhance the Passenger Presence System (PPS) when an infant car seat is properly restrained on the front passenger seat. The seat belt tension sensor is a 3-wire potentiometer mounted on the lower seat belt anchor and provides an input to the PPS module. When an infant car seat is properly restrained on the front passenger seat, the seat belt is tightly secured through the infant car seat. The seat belt pulls on the tension sensor and changes the voltage signal to the PPS module. The PPS module uses the voltage signal to help determine if a tightly belted infant car seat is installed. The PPS uses the inputs from the seat belt tension sensor and the passenger presence sensor to determine if the passenger instrument panel air bag should be suppressed or enabled.

Seat Belt Pretensioner (Retractor)

The seat belt pretensioner (driver and passenger) consist of a housing, seat belt retractor (located in the B-pillar), seat belt webbing, an initiator, and a canister of gas generating materials. To view the locations of the seat belt pretentioners refer to SIR Identification Views . The initiator is part of the seat belt pretensioner deployment loop. When the vehicle is involved in a collision of sufficient force, the SDM causes current to flow through the seat belt deployment loops to the initiator. Current passing through the initiator ignites the material in the canister producing a rapid generation of gas. The gas produced from this reaction deploys the seat belt pretensioners which removes all of the slack in the seat belts. Depending on the severity of the collision, the seat belt pretensioners may deploy without the frontal air bags deploying, or they will deploy immediately before the frontal air bags deploy. A shorting bar (if equipped) is located in the connector.

Impact Sensors

This vehicle contains anywhere from 1-6 impact sensors depending on option content. The options are as follows

1. SUV has 6 impact sensors: 2 in the front and 4 in the doors
2. Light Duty Regular Cab has 4 impact sensors: 2 in the front and 2 in the doors
3. Light Duty Extended Cab has 6 impact sensors: 2 in the front and 4 in the doors
4. Light Duty Crew Cab has 6 impact sensors: 2 in the front and 4 in the doors
5. Heavy Duty Regular Cab has 1 or 3 impact sensors: one, in the center front, or three, one in the center and two in the doors
6. Heavy Duty Extended Crew Cab has 1 or 5 impact sensors: one, in the center front, or three, one in the center and four in the doors

To view the locations of the impact sensors refer to SIR Identification Views . The impact sensors contain a sensing device which monitors vehicle acceleration and velocity changes to detect side collisions that are severe enough to warrant air bag deployment. The impact sensor are not part of the deployment loop, but instead provide input to the 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 appropriate air bags.

Passenger Presence Detection System and Passenger Air Bag Indicator (If Equipped)

Note. The passenger presence system (PPS) is a calibrated unit. When replacing the assembly all parts in the service kit must remain together. Do not mix any of the old parts with the new parts. After repairing or replacing the PPS, the preload test must be performed in order to function properly.

The passenger presence detection system (PPS) is used to monitor the type of occupant that is sitting in the front passenger seat and communicate the status to the inflatable restraint sensing and diagnostic module (SDM). The SDM then uses this information to determine whether to enable or suppress the deployment of the passenger instrument panel air bag. The PPS consists of an electronic control module, a sensor mat in the seat, a harness, and PASSENGER AIR BAG ON/OFF indicators. The PPS transmits and receives a low-level electric field. The measured capacitance value of this field is used to determine the type of occupant sitting in the front passenger seat. If the measured capacitance is less than a calibrated value, then the PPS module will send a serial data signal to the SDM to disable the passenger instrument panel air bag. If the measured capacitance is greater than a calibrated value, then the PPS module will send a serial data signal to the SDM to enable the passenger instrument panel air bag. The SDM will notify the customer of the enable/disable status by illuminating one of the PASSENGER AIR BAG ON/OFF indicator. The PPS monitors itself for faults and will displays diagnostic trouble codes (DTCs) on the scan tool. When a fault is detected, the PPS module sends out a message to the SDM. The SDM responds by sending a command message to the IPC to illuminate the SIR system AIR BAG indicator.

Passenger Air Bag Disable Switch (If Equipped)

The passenger air bag disable switch is used to turn the passenger instrument panel air bag on or off. The customer can decide to turn the passenger air bag off by turning this switch on. When the SDM sees a ground circuit from this switch the passenger air bag is turned off.

Seat Belt Indicators

The seat belt indicators are controlled through the inflatable restraint sensing and diagnostic module (SDM). For further information on seat belt indicators refer to Seat Belt System Description and Operation .

Special Tools

Illustration Tool Number/Description J 38715-A Driver or Passenger SIR Load Tool J 38826 SIR Deployment Harness J 39401-B SIR Deployment Fixture

See also:
• Diagnostic System Check - Vehicle
• Strategy Based Diagnosis
• Diagnostic Procedure Instructions
• WIRING SYSTEMS AND POWER MANAGEMENT - COMPONENT CONNECTOR END VIEWS - INDEX
• Circuit Testing
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Connector Repairs
• Control Module References
• Diagnostic Repair Verification
• SIR/SRS Wiring Repairs
• Front Seat Belt Buckle Replacement
• Diagnostic Trouble Code (DTC) List - Vehicle
• Inflatable Restraint Sensing and Diagnostic Module Programming and Setup
• Scan Tool Does Not Communicate with Low Speed GMLAN Device
• Checking Aftermarket Accessories
• Electrical Center Identification Views
• Battery Negative Cable Disconnection and Connection (TP2)
• SIR Warning
• Lifting and Jacking the Vehicle
• Fastener Caution
• Upper Extension Trim Panel Replacement
• Front Floor Console Replacement (without RPO SLT)
• Radio Front Floor Console Speaker Replacement
• SIR Inflator Module Handling and Storage Warning
• Steering Wheel Replacement
• Front Seat Replacement - Bucket
• Front Seat Adjuster Replacement (Power)
• Headlining Trim Panel Replacement (Crew Cab)
• Headlining Trim Panel Replacement (Extended Cab)
• High Voltage System Inspection
• Repairs and Inspections Required After a Collision
• Component Connector End Views
• SIR Disabling and Enabling
• DTC B0012 or B0013
• Steering Wheel Airbag Coil Replacement
• SIR Identification Views
• Inflatable Restraint Steering Wheel Module Coil Centering