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Part 1




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

Pinpoint Tests

Pinpoint Test C: 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 all front air bag module circuits (loop) for the following faults:

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

If a fault is detected, the RCM will store DTC B2293 in memory and send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

As the RCM continuously monitors all front air bag module circuits for resistance, it expects a normal resistance for the driver and passenger air bag modules loop 1 and 2, between 1.31 to 4.29 ohms.

If a loop resistance for the driver and/or passenger air bag loop 1 and/or 2 is between 0.9 and 1.31 ohms or between 4.29 and 5 ohms, there exists a strong potential for an intermittent fault, a DTC may or may not set. The RCM will also set an on-demand DTC if the loop resistance is less than 0.9 ohm or greater than 5 ohms.





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

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



PINPOINT TEST C: DTC B2293

WARNING: Do not handle, move or change the original horizontal mounting position of the restraints control module (RCM) while the RCM is connected and the ignition switch is ON. Failure to follow this instruction may result in the accidental deployment of the Safety Canopy(R) and cause serious personal injury or death.

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 making 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: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.

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C1 RETRIEVE RCM DTCs


- 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 PID list in Normal Operation to view 2293 fault PIDs.
- Do any on-demand DTC B2293 fault PIDs indicate a fault?

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

Using the fault PIDs recorded, GO to the appropriate pinpoint test step.

For 2293_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side), GO to C2.

For 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side), GO to C2.

For (2293_31_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side), GO to C10.

For driver air bag module loop 1 with a short to battery fault (2293_30_OD), GO to C13.

For 2293_20_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Driver Side), GO to C15.

For 2293_21_OD (Air Bag Circuit Open - Loop No. 2, Front Driver Side), GO to C15.

For 2293_23_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Driver Side), GO to C23.

For 2293_22_OD (Air Bag Circuit Short to Battery - Loop No. 2, Front Driver Side), GO to C26.

For 2293_24_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side), GO to C28.

For 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side), GO to C28.

For 2293_27_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side), GO to C34.

For 2293_26_OD (Air Bag Circuit Short to Battery - Loop No. 1, Front Passenger Side), GO to C36.

For 2293_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side), GO to C37.

For 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side), GO to C37.

For 2293_19_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side), GO to C43.

For 2293_18_OD (Air Bag Circuit Short to Battery - Loop No. 2, Front Passenger Side), GO to C45.

No
This is an intermittent fault when present as a Continuous Memory Diagnostic Trouble Code (CMDTC) only. The fault condition is not present at this time.

Using the fault PIDs recorded, GO to the appropriate pinpoint test step.

For 2293_28_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side) or 2293_20_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Driver Side), GO to C50.

For 2293_29_CM (Air Bag Circuit Open - Loop No. 1, Front Driver Side) or 2293_21_CM (Air Bag Circuit Open - Loop No. 2, Front Driver Side), GO to C50.

For 2293_31_CM (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side) or 2293_23_CM (Air Bag Circuit Short to Ground - Loop No. 2, Front Driver Side), GO to C51.

For 2293_30_CM (Air Bag Circuit Short to Battery - Loop No. 1, Front Driver Side) or 2293_22_CM (Air Bag Circuit Short to Battery - Loop No. 2, Front Driver Side), GO to C53.

For 2293_24_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side) or 2293_16_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side), GO to C50.

For 2293_25_CM (Air Bag Circuit Open - Loop No. 1, Front Passenger Side) or 2293_17_CM (Air Bag Circuit Open - Loop No. 2, Front Passenger Side), GO to C50.

For 2293_27_CM (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side) or 2293_19_CM (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side), GO to C52.

For 2293_26_CM (Air Bag Circuit Short to Battery - Loop No. 1, Front Passenger Side) or 2293_18_CM (Air Bag Circuit Short to Battery - Loop No. 2, Front Passenger Side), GO to C54.

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C2 CHECK THE DRIVER AIR BAG MODULE LOOP 1 RESISTANCE (D_ABAGR) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM.
- Enter the following diagnostic mode on the scan tool: D_ABAGR (Driver Air Bag) Resistance PID.
- Is the resistance PID value between 1.31 and 4.29 ohms?

Yes
GO to C49.

No
GO to C3.

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C3 CHECK THE DRIVER AIR BAG MODULE LOOP 1 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.
- With the driver air bag in its mounted position, continue monitoring the D_ABAGR resistance PID while carrying out a harness test of the driver air bag circuits and accessible connectors (including any inline connectors) by wiggling and flexing the wire harness, connectors, tilting and rotating the steering wheel frequently.
- Does the resistance PID value read between 1.31 and 4.29 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 C56.

No
If the D_ABAGR PID is less than 1.31 ohms, GO to C4.

If the D_ABAGR PID is greater than 4.29 ohms, GO to C7.

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C4 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR 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 (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a low resistance to an open circuit fault?

Yes
GO to C46.

No
GO to C5.

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C5 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR STATUS CHANGE (LOW RESISTANCE INDICATED) (DRIVER AIR BAG REMOVED)


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: 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_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module/clockspring disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a low resistance to an open circuit fault?

Yes
GO to C48.

No
GO to C6.

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C6 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 resistance between RCM C310a pin 3 and C310a pin 4, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR101 (VT/BN) and RR101 (YE/GN). GO to C56.

No
GO to C49.

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C7 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR 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.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Connect a fused jumper between driver air bag module loop 1 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 (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module loop 1 circuits shorted together, a low resistance fault would normally be retrieved on loop 1. Loop 2 will show an open circuit fault due to the driver air bag being disconnected.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a open circuit to a low resistance fault?

Yes
GO to C46.

No
GO to C8.

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C8 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR STATUS CHANGE (OPEN 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 jumper wire from driver air bag module loop 1 electrical connector.
- Disconnect: Clockspring C218a.
- Connect a fused jumper between clockspring C218a-1, circuit CR101 (VT/BN), harness side and clockspring C218a-9, circuit RR101 (YE/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_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module loop 1 circuits shorted together, a low resistance fault would normally be retrieved on loop 1. Loop 2 will show an open circuit fault due to the driver air bag being disconnected.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a open circuit to a low resistance fault?

Yes
GO to C48.

No
GO to C9.

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C9 CHECK THE DRIVER AIR BAG MODULE LOOP 1 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 jumper wire from the clockspring connector.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310a, harness side and clockspring C218a, harness side using the following chart.









- Are the resistances less than 0.5 ohm?

Yes
GO to C49.

No
REPAIR circuit CR101 (VT/BN) or RR101 (YE/GN). GO to C56.

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C10 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR 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 (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a short to ground to an open circuit fault?

Yes
GO to C46.

No
GO to C11.

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C11 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR 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.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- 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_31_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the clockspring disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a short to ground to an open circuit fault?

Yes
GO to C48.

No
GO to C12.

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C12 CHECK DRIVER AIR BAG MODULE LOOP 1 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 resistance between clockspring:
- C218a-1, circuit CR101 (VT/BN), harness side and ground.
- C218a-9, circuit RR101 (YE/GN), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to C49.

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 C56.

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C13 CHECK THE DRIVER AIR BAG MODULE LOOP 1 FAULT PID FOR STATUS CHANGE (SHORT TO BATTERY 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_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- 2293_30_OD (Air Bag Circuit Short to Battery - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module/clockspring disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PID change from indicating a short to battery to an open circuit fault?

Yes
GO to C48.

No
GO to C14.

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C14 CHECK DRIVER AIR BAG MODULE LOOP 1 CIRCUITS FOR A SHORT TO VOLTAGE (CLOCKSPRING DISCONNECTED)


- 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 voltage between clockspring:
- C218a-1, circuit CR101 (VT/BN), harness side and ground.
- C218a-9, circuit RR101 (YE/GN), harness side and ground.




- Is voltage present on either circuit?

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 C56.

No
GO to C49.

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C15 CHECK THE DRIVER AIR BAG MODULE LOOP 2 RESISTANCE (D_ABAGR2) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM.
- Enter the following diagnostic mode on the scan tool: D_ABAGR2 (Driver Air Bag #2 Resistance) Resistance PID.
- Is the resistance PID value between 1.31 and 4.29 ohms?

Yes
GO to C49.

No
GO to C16.

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