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Part 1




Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)

Pinpoint Tests

Pinpoint Test J: LFC 19/21/ DTC B2293

Refer to Wiring Diagram Set 46, Supplemental Restraint System for schematic and connector information. Diagrams By Number

Normal Operation

The Restraints Control Module (RCM) continuously monitors the driver and passenger air bag module circuits for the following:

- Resistance out of range
- Unacceptable voltage
- Short to ground

The RCM will set and store DTC B2293 in memory if any of these conditions are detected to be outside of their respectful range. If the RCM detects one of the following faults on any of the front air bag module circuits, it will store DTC B2293 in memory and send a message to the Instrument Cluster (IC) module to flash Lamp Fault Code (LFC) 19 or 21 (or higher priority code if one exists) on the air bag warning indicator.

As the RCM continuously monitors driver and passenger air bag module circuits for resistance, it expects a normal resistance between 1.36 to 3.96 ohms for the driver air bag module and between 1.50 to 3.04 ohms for the passenger air bag module.

For the driver air bag module, if a loop resistance is between 1.36 and 1.84 ohms or between 3.96 and 4.70 ohms, a DTC may or may not set, yet there exists a strong potential for an intermittent fault. The RCM will also set and store a DTC if the loop resistance is less than 1.36 ohms or greater than 4.70 ohms.

For the passenger air bag module, if a loop resistance is between 1.04 and 1.50 ohms or between 3.04 and 3.72 ohms, a DTC may or may not set, yet there exists a strong potential for an intermittent fault. The RCM will also set and store a DTC if the loop resistance is less than 1.04 ohms or greater than 3.72 ohms.





a Fault PIDs that end in OD indicate an on-demand status and are associated with DTC B2293. Fault PIDs that end in CM indicate continuous memory status and are associated with DTC B2293.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Clockspring
- Driver air bag module
- Passenger air bag module
- RCM



PINPOINT TEST J: LFC 19/21 DTC B2293

WARNING: Always tighten the fasteners of the restraints control module (RCM) and impact sensor (if equipped) to the specified torque. Failure to do so may result in incorrect restraint system operation, which increases the risk of personal injury or death in a crash.

WARNING: Never probe the electrical connectors on air bag, Safety Canopy(R) or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.

NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when taking measurements. Failure to use the correct probe adapter(s) may damage the connector.

Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test. Inspection and Verification

NOTE: Supplemental Restraint System (SRS) components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

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J1 RETRIEVE RCM DTCs


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM View and Record All 2293 Fault PIDs.
- Refer to the PID list in Normal Operation to view B2293 fault PIDs.
- Do any on-demand DTC B2293 fault PIDs indicate a fault?

Yes
This fault cannot be cleared until it is corrected and the DTC is no longer retrieved on-demand during self-test.

For 2293_28_OD, GO to J2.

For 2293_29_OD, GO to J2.

For 2293_31_OD, GO to J10.

For 2293_30_OD, GO to J13.

For 2293_24_OD, GO to J15.

For 2293_25_OD, GO to J15.

For 2293_27_OD, GO to J21.

For 2293_26_OD, GO to J23.

No
This is an intermittent fault when present as a Continuous Memory Diagnostic Trouble Code (CMDTC) only.

For 2293_28_CM, GO to J28.

For 2293_29_CM, GO to J28.

For 2293_31_CM, GO to J29.

For 2293_30_CM, GO to J31.

For 2293_24_CM, GO to J28.

For 2293_25_CM, GO to J28.

For 2293_27_CM, GO to J30.

For 2293_26_CM, GO to J32.

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J2 CHECK THE DRIVER AIR BAG MODULE RESISTANCE (D_ABAGR) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM PID.
- Enter the following diagnostic mode on the scan tool: D_ABAGR PID.
- Does the PID value read between 1.84 and 3.96 ohms?

Yes
GO to J27.

No
GO to J3.

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J3 MONITOR THE DRIVER AIR BAG MODULE RESISTANCE (D_ABAGR) PID WHILE CARRYING OUT A HARNESS TEST


- NOTE: Do not remove the driver air bag module from its mounted position at this time.
- Continue monitoring the D_ABAGR PID while carrying out a harness test of the driver air bag circuits and accessible connectors (including any in-line connectors) by wiggling and flexing the wire harness, connectors and rotating the steering wheel frequently.
- Does the PID value read between 1.84 and 3.96 ohms while carrying out the harness test?

Yes
DEPOWER the SRS and REPAIR the connector, terminals or wire harness or INSTALL a new clockspring as needed. REFER to Clockspring Service and Repair.
Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

GO to J34.

No
For PID value less than 1.84 ohms, GO to J4.

For PID value greater than 3.96 ohms, GO to J7.

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J4 CHECK DRIVER AIR BAG DTC FOR FAULT STATUS CHANGE (LOW RESISTANCE INDICATED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 2293_28_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the driver air bag module disconnected, open circuit faults would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a low resistance to an open circuit fault?

Yes
GO to J24.

No
GO to J5.

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J5 CHECK DRIVER AIR BAG MODULE DTC FOR FAULT STATUS CHANGE (LOW RESISTANCE INDICATED) (CLOCKSPRING DISCONNECTED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Disconnect: Clockspring C218a.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 2293_28_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the driver air bag module/clockspring disconnected, open circuit faults would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a low resistance to an open circuit fault?

Yes
GO to J26.

No
GO to J6.

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J6 CHECK THE RCM FOR LOW RESISTANCE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310A and C310B.
- Measure the resistance between RCM C310A pins 3 and 4, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR101 (VT/BN) and RR101 (YE/GN). GO to J34.

No
GO to J27.

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J7 CHECK DRIVER AIR BAG DTC FOR FAULT STATUS CHANGE AN (OPEN INDICATED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Connect a fused jumper wire between driver air bag module electrical connector pin-1, harness side and pin-2, harness side.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM View and Record The Following Fault PIDs.
- 2293_28_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the driver air bag module circuits shorted together, a low resistance fault would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a open circuit to a low resistance fault?

Yes
GO to J24.

No
GO to J8.

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J8 CHECK THE DRIVER AIR BAG MODULE CIRCUITS FOR AN OPEN BETWEEN THE CLOCKSPRING AND RCM


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Remove the fused jumper wire from driver air bag module electrical connector.
- Disconnect: Clockspring C218a.
- Connect a fused jumper wire between clockspring C218a-2, circuit CR101 (VT/BN), harness side and clockspring C218a-10, circuit RR101 (YE/GN), harness side.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 2293_28_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the driver air bag module circuits shorted together, a low resistance fault would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a open circuit to a low resistance fault?

Yes
GO to J26.

No
GO to J9.

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J9 CHECK THE DRIVER AIR BAG MODULE CIRCUITS FOR AN OPEN BETWEEN THE CLOCKSPRING AND RCM


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Remove the fused jumper wire from the clockspring connector.
- Disconnect: RCM C310A and C310B.
- Measure the resistance between:
- RCM C310A-4, circuit CR101 (VT/BN), harness side and clockspring C218A-2, circuit CR101 (VT/BN), harness side.
- RCM C310A-3, circuit RR101 (YE/GN), harness side and clockspring C218A-10, circuit RR101 (YE/GN), harness side.




- Are the resistances less than 0.5 ohm?

Yes
GO to J27.

No
REPAIR circuit CR101 (VT/BN) or RR101 (YE/GN). GO to J34.

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J10 CHECK THE DRIVER AIR BAG DTC FOR FAULT STATUS CHANGE (SHORT TO GROUND INDICATED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 2293_31_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the driver air bag module disconnected, open circuit faults would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a short to ground to an open circuit fault?

Yes
GO to J24.

No
GO to J11.

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J11 CHECK DRIVER AIR BAG DTC FOR FAULT STATUS CHANGE (SHORT TO GROUND INDICATED) (CLOCKSPRING DISCONNECTED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Disconnect: Clockspring C218a.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 2293_31_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the clockspring disconnected, open circuit faults would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a short to ground to an open circuit fault?

Yes
GO to J26.

No
GO to J12.

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J12 CHECK DRIVER AIR BAG MODULE CIRCUITS FOR A SHORT TO GROUND


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310A and C310B.
- Measure the resistance between clockspring:
- C218a-2, circuit CR101 (VT/BN), harness side and ground.
- C218a-10, circuit RR101 (YE/GN), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to J27.

No
Due to the shorting bar feature in the RCM electrical connector, the fault can exist in either circuit. Do not remove or defeat the shorting bar.

REPAIR circuit CR101 (VT/BN) or RR101 (YE/GN). GO to J34.

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J13 CHECK DRIVER AIR BAG DTC FOR FAULT STATUS CHANGE (SHORT TO VOLTAGE INDICATED) (CLOCKSPRING DISCONNECTED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Disconnect: Clockspring C218a.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record The Following Fault PIDs.
- 2293_30_OD
- 2293_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the driver air bag module/clockspring disconnected, open circuit faults would normally be retrieved.
- Did the driver air bag module fault PIDs change from indicating a short to battery to an open circuit fault?

Yes
GO to J26.

No
GO to J14.

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J14 CHECK DRIVER AIR BAG MODULE CIRCUITS FOR A SHORT TO VOLTAGE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310A and C310B.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Measure the voltage between clockspring:
- C218a-2, circuit CR101 (VT/BN), harness side and ground.
- C218a-10, circuit RR101 (YE/GN), harness side and ground.




- Is any voltage present?

Yes
Due to the shorting bar feature in the RCM electrical connector, the fault can exist in either circuit. Do not remove or defeat the shorting bar.

REPAIR circuit CR101 (VT/BN) or RR101 (YE/GN). GO to J34.

No
GO to J27.

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J15 CHECK THE PASSENGER AIR BAG MODULE RESISTANCE (P_ABAG) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM PID.
- Enter the following diagnostic mode on the scan tool: P_ABAGR PID.
- Does the PID value read between 1.50 and 3.04 ohms?

Yes
GO to J27.

No
GO to J16.

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J16 MONITOR THE PASSENGER AIR BAG MODULE RESISTANCE (P_ABAG) PID WHILE CARRYING OUT A HARNESS TEST


NOTE: Do not remove the passenger air bag module from its mounted position at this time.

- With the passenger air bag in its mounted position, continue monitoring the P_ABAGR PID while carrying out a harness test of the passenger air bag module circuits and accessible connectors (including any in-line connectors), by wiggling connectors and flexing the wire harness.
- Does the PID value read between 1.50 and 3.04 ohms while carrying out the harness test?

Yes
DEPOWER the SRS and REPAIR the connector, terminals or wire harness as needed.
Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

GO to J34.

No
For PID value less than 1.50 ohms, GO to J17.

For PID value greater than 3.04 ohms, GO to J19.

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J17 CHECK PASSENGER AIR BAG DTC FOR FAULT STATUS CHANGE (LOW RESISTANCE INDICATED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Air Bag Module C256.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM View and Record The Following Fault PIDs.
- 2293_24_OD
- 2293_25_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved.
- Did the passenger air bag module fault PIDs change from indicating a low resistance to an open circuit fault?

Yes
GO to J25.

No
GO to J18.

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J18 CHECK THE RCM FOR LOW RESISTANCE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310A and C310B.
- Measure the resistance between RCM C310A pins 1 and 2, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR103 (GY/BU) and RR103 (VT/GN). GO to J34.

No
GO to J27.

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J19 CHECK PASSENGER AIR BAG DTC FOR FAULT STATUS CHANGE (OPEN INDICATED)


NOTE: This pinpoint test step will attempt to change the fault reported by the RCM by inducing a different fault condition. If the fault reported changes, this indicates the RCM is functioning correctly and is not the source of the fault.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Air Bag Module C256.
- Connect a fused jumper wire between passenger air bag module C256-1, circuit CR103 (GY/BU), harness side and C256-2, circuit RR103 (VT/GN), harness side.
- Repower the SRS. Do not prove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM View and Record The Following Fault PIDs.
- 2293_24_OD
- 2293_25_OD
- DIAGNOSTIC TIP: When viewing DTC B2293 fault PIDs with the passenger air bag module circuits shorted together, a low resistance fault would normally be retrieved.
- Did the passenger air bag module fault PIDs change from indicating an open circuit to a low resistance fault?

Yes
GO to J25.

No
GO to J20.

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J20 CHECK PASSENGER AIR BAG MODULE CIRCUITS FOR AN OPEN


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: RCM C310A and C310B.
- Measure the resistance between:
- RCM C310A-1, circuit CR103 (GY/BU), harness side and passenger air bag module C256-2, circuit CR103 (GY/BU), harness side.
- RCM C310A-2, circuit RR103 (VT/GN), harness side and passenger air bag module C256-1, circuit RR103 (VT/GN), harness side.




- Are the resistances less than 0.5 ohm?

Yes
GO to J27.

No
REPAIR circuit CR103 (GY/BU) or RR103 (VT/GN). GO to J34.

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