• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
• Review Strategy Based Diagnosis for an overview of the diagnostic approach.
• Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Under certain vehicle events involving an impact or predicted roll over event with sufficient force the Inflatable Restraint Sensing and Diagnostic Module will allow current to flow through the deployment loop in order to deploy an air bag or pretensioner. on vehicles equipped with shorting bars there are 2 shorting bars which will short together control circuits, when the connector is disconnected. This will help to prevent unwanted deployment of the air bag or pretensioner during servicing.

Ignition voltage is between 9–16 V.

The pretensioner control circuit is shorted to voltage for 2 seconds.

The pretensioner control circuit is shorted to ground for 2 seconds.

The pretensioner control circuit is open for 2 seconds.

The pretensioner deployment loop resistance is greater than 4.2 Ω for 2 seconds.

The pretensioner deployment loop resistance is less than 1.4 Ω for 2 seconds.

• The Inflatable Restraint Sensing and Diagnostic Module requests the Instrument Cluster to illuminate the AIR BAG indicator.
• The Inflatable Restraint Sensing and Diagnostic Module will store a DTC, however if an event occurs the system will still attempt deployments.

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

Refer to SIR Service Precautions.

Refer to SIR Disabling and Enabling.

An incorrectly installed connector position assurance (CPA) or incorrectly seated connector can cause a shorting bar (If Equipped) to short both control circuits together. For vehicles equipped with shorting bars 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 may be used in the locations listed below:

• Driver and passenger anchor or retractor pretensioners
• Inline harness connectors
• Harness side of the inflatable restraint sensing and diagnostic module connector

Terminal fretting or incorrectly seated connectors 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. DTCs of deployment loops which are in the seat can occur because of stress or damage to the harness due to seat movement. Move the seat to the full extent of travel while using the scan tool to observe deployment type loop parameters.

SIR Schematics

Master Electrical Component List

Supplemental Inflatable Restraint System Description and Operation

• Circuit Testing
• Testing for Intermittent Conditions and Poor Connections
• Wiring Repairs
• Connector Repairs

Control Module References for scan tool information

EL-38125-580 Terminal Release Tool Kit

• Refer to SIR Service Precautions.

Note: The condition may be intermittent and require driving the vehicle, then reviewing the snapshot to verify resistance parameters do not drop out or spike. Refer to Testing for Intermittent Conditions and Poor Connections

1. Verify the appropriate scan tool Deployment Loop Resistance parameters stay consistently between 2.1–4.0 Ω without any spikes or dropouts for each component listed below:
• F112D Seat Belt Retractor Pretensioner
• F112P Seat Belt Retractor Pretensioner
• F113D Seat Belt Anchor Pretensioner
• F113P Seat Belt Anchor Pretensioner
• If less than 2.1 or greater than 4.0 Ω

  Refer to Circuit/System Testing.

• If within 2.1 and 4.0 Ω
2. A fault is not currently present and may be an intermittent condition.

1. Vehicle / Ignition OFF,
2. Verify the SIR system is disabled.
3. Disconnect the scan tool.
4. Disconnect the appropriate Component:
• F112D Seat Belt Retractor Pretensioner
• F112P Seat Belt Retractor Pretensioner
• F113D Seat Belt Anchor Pretensioner
• F113P Seat Belt Anchor Pretensioner
5. Test for greater than 25 Ω between the appropriate control circuit terminals listed below:
• F112 Seat Belt Retractor Pretensioner terminals 1 and 2
• F113 Seat Belt Anchor Pretensioner terminals 1 and 2
• If 25 Ω or less
1. Disconnect the harness connector at the K36 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 on vehicles equipped 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.

2. Test for infinite resistance between the 2 control circuits.
• If less than infinite resistance, repair the short between the two circuits.
• If infinite resistance, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If greater than 25 Ω
6. Vehicle / Ignition ON.
7. Test for less than 11 V between the control circuit terminals listed below and ground:
• F112D Seat Belt Retractor Pretensioner terminal 1 and terminal 2
• F112P Seat Belt Retractor Pretensioner terminal 1 and terminal 2
• F113D Seat Belt Anchor Pretensioner terminal 1 and terminal 2
• F113P Seat Belt Anchor Pretensioner terminal 1 and terminal 2
• If 11 V or greater
1. Vehicle / Ignition OFF.
2. Verify the SIR system is disabled,
3. Disconnect the X2 harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
4. Vehicle / Ignition- ON.
5. Test for less than 1 V between each 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. Vehicle / Ignition OFF.
9. Verify the SIR system is disabled,
10. Test for greater than 25 Ω between the control circuit terminals listed below and ground:
• F112D Seat Belt Retractor Pretensioner terminal 1 and terminal 2
• F112P Seat Belt Retractor Pretensioner terminal 1 and terminal 2
• F113D Seat Belt Anchor Pretensioner terminal 1 and terminal 2
• F113P Seat Belt Anchor Pretensioner terminal 1 and terminal 2
• If 25 Ω or less
1. Verify the SIR system is disabled,
2. Disconnect the harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
3. Test for infinite resistance between each control circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If greater than 25 Ω
11. Verify the SIR system is disabled.
12. Install a 3 A fused jumper wire between the appropriate component control circuit listed helow:
• F112D Seat Belt Retractor Pretensioner terminal 1 and terminal 2
• F112P Seat Belt Retractor Pretensioner terminal 1 and terminal 2
• F113D Seat Belt Anchor Pretensioner terminal 1 and terminal 2
• F113P Seat Belt Anchor Pretensioner terminal 1 and terminal 2
13. Vehicle / Ignition ON.
14. Verify the scan tool Deployment Loop Resistance parameter is less than 2 Ω.
• If 2 Ω or greater
1. Vehicle OFF.
2. Verify the SIR system is disabled,
3. Disconnect the harness connector at the K36 Inflatable Restraint Sensing and Diagnostic Module.
4. Test for less than 2 Ω in each control circuit end to end.
• If 2  Ω or greater, repair the open/high resistance in the circuit.
• If less than 2 Ω, replace the K36 Inflatable Restraint Sensing and Diagnostic Module.
• If less than 2 Ω
15. Vehicle / Ignition OFF.
16. Verify the SIR system is disabled,
17. Connect the appropriate Component:
• F112D Seat Belt Retractor Pretensioner
• F112P Seat Belt Retractor Pretensioner
• F113D Seat Belt Anchor Pretensioner
• F113P Seat Belt Anchor Pretensioner
18. Vehicle / Ignition ON, vehicle in service mode.
19. Clear DTCs. Operate the vehicle within the Conditions for Running the DTC.
20. Verify DTC B0015, B001A, B001B, or B0022 is not set.
• If B0015, B001A, B001B, or B0022 is set

  Replace the appropriate F112 Seat Belt Retractor Pretensioner or F113 Seat Belt Anchor Pretensioner.

• If DTC B0015, B001A, B001B, or B0022 is not set
21. All OK.

Perform the Diagnostic Repair Verification after completing the repair.

• Front Seat Belt Anchor Plate Tensioner Replacement
• Front Seat Belt Retractor Replacement
• Control Module References for Inflatable Restraint Sensing and Diagnostic Module replacement, programming and setup