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Part 3




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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C31 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 1 and C310a pin 2, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR103 (GY/BU) and RR103 (VT/GN). GO to C56.

No
GO to C49.

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C32 CHECK THE PASSENGER AIR BAG MODULE LOOP 1 FAULT PID 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 between passenger air bag module C256-4, circuit CR103 (GY/BU), harness side and C256-3, 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 (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side)
- 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger 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 passenger air bag being disconnected.
- Did the passenger air bag module loop 1 on-demand fault PID change from indicating an open circuit to a low resistance fault?

Yes
GO to C47.

No
GO to C33.

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C33 CHECK THE PASSENGER AIR BAG MODULE LOOP 1 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.
- Remove the jumper wire from passenger air bag module C256.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310a-1, circuit CR103 (GY/BU), harness side and passenger air bag module C256-3, circuit CR103 (GY/BU), harness side.




- Measure resistance between RCM C310a-2, circuit RR103 (VT/GN), harness side and passenger air bag module C256-4, circuit RR103 (VT/GN), harness side.




- Are the resistances less than 0.5 ohm?

Yes
GO to C49.

No
REPAIR circuit CR103 (GY/BU) or RR103 (VT/GN). GO to C56.

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C34 CHECK THE PASSENGER AIR BAG MODULE LOOP 1 FAULT PID 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.
- 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_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side)
- 2293_27_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the passenger air bag module loop 1 on-demand fault PID change from indicating a short to ground to an open circuit fault?

Yes
GO to C47.

No
GO to C35.

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C35 CHECK PASSENGER 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 passenger air bag module:
- C256-3, circuit CR103 (GY/BU), harness side and ground.
- C256-4, circuit RR103 (VT/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 CR103 (GY/BU) or RR103 (VT/GN). GO to C56.

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C36 CHECK PASSENGER AIR BAG MODULE LOOP 1 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: Passenger Air Bag Module C256.
- 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 passenger air bag module:
- C256-3, circuit CR103 (GY/BU), harness side and ground.
- C256-4, circuit RR103 (VT/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 CR103 (GY/BU) or RR103 (VT/GN). GO to C56.

No
GO to C49.

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C37 CHECK THE PASSENGER AIR BAG MODULE LOOP 2 RESISTANCE (P_ABAGR2) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM.
- Enter the following diagnostic mode on the scan tool: P_ABAGR2 Resistance PID.
- Is the resistance PID value between 1.31 and 4.29 ohms?

Yes
GO to C49.

No
GO to C38.

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C38 CHECK THE PASSENGER AIR BAG MODULE LOOP 2 RESISTANCE (P_ABAGR2) 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_ABAGR2 resistance PID while carrying out a harness test of the passenger air bag module circuits and accessible connectors (including any inline connectors), by wiggling connectors and flexing the wire harness.
- 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 as needed.
Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to C56.

No
If the P_ABAGR2 PID is less than 1.31 ohms, GO to C39.

If the P_ABAGR2 PID is greater than 4.29 ohms, GO to C41.

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C39 CHECK THE PASSENGER AIR BAG MODULE LOOP 2 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.
- 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_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side)
- 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the passenger air bag module loop 2 on-demand fault PID change from indicating a low resistance to an open circuit fault?

Yes
GO to C47.

No
GO to C40.

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C40 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 5 and C310a pin 6, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR104 (YE/GY) and RR104 (WH/BU). GO to C56.

No
GO to C49.

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C41 CHECK THE PASSENGER AIR BAG MODULE LOOP 2 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.
- Disconnect: Passenger Air Bag Module C256.
- Connect a fused jumper between passenger air bag module C256-1, circuit CR104 (YE/GY), harness side and C256-2, circuit RR104 (WH/BU), 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_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side)
- 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module loop 2 circuits shorted together, a low resistance fault would normally be retrieved on loop 2. Loop 1 will show an open circuit fault due to the passenger air bag module being disconnected.
- Did the passenger air bag module loop 2 on-demand fault PID change from indicating an open circuit to a low resistance fault?

Yes
GO to C47.

No
GO to C42.

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C42 CHECK THE PASSENGER AIR BAG MODULE LOOP 2 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.
- Remove the jumper wire from passenger air bag module C256.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310a, harness side and passenger air bag module C256, harness side using the following chart.









- Are the resistances less than 0.5 ohm?

Yes
GO to C49.

No
REPAIR circuit CR104 (YE/GY) or RR104 (WH/BU). GO to C56.

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C43 CHECK THE PASSENGER AIR BAG MODULE LOOP 2 FAULT PID 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.
- 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_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side)
- 2293_19_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the passenger air bag module loop 2 on-demand fault PID change from indicating a short to ground to an open circuit fault?

Yes
GO to C47.

No
GO to C44.

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C44 CHECK PASSENGER AIR BAG MODULE LOOP 2 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 passenger air bag module:
- C256-1, circuit CR104 (YE/GY), harness side and ground.
- C256-2, circuit RR104 (WH/BU), 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 CR104 (YE/GY) or RR104 (WH/BU). GO to C56.

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C45 CHECK PASSENGER AIR BAG MODULE LOOP 2 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: Passenger Air Bag Module C256.
- 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 passenger air bag module:
- C256-1, circuit CR104 (YE/GY), harness side and ground.
- C256-2, circuit RR104 (WH/BU), 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 CR104 (YE/GY) or RR104 (WH/BU). GO to C56.

No
GO to C49.

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C46 CONFIRM THE DRIVER AIR BAG MODULE FAULT


NOTE: Make sure all restraint system components and the RCM electrical connectors are connected before carrying out the on-demand self-test. If not, erroneous DTCs will be recorded.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Install 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 All 2293 Fault PIDs.
- Refer to PID list in Normal Operation to view 2293 fault PIDs.
- Does the original on-demand DTC B2293 fault PID indicate a fault?

Yes
INSTALL a new driver air bag module. REFER to Driver Air Bag Module Driver Air Bag Module. GO to C56.

No
In the process of diagnosing the fault, the fault condition has become intermittent. Using the fault PIDs recorded, GO to the appropriate pinpoint test step and CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of electrical connectors that were disconnected.

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.

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C47 CONFIRM THE PASSENGER AIR BAG MODULE FAULT


NOTE: Make sure all restraint system components and the RCM electrical connectors are connected before carrying out the on-demand self test. If not, erroneous DTCs will be recorded.

- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Connect: Passenger Air Bag Module C256 (if previously disconnected).
- 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 All 2293 Fault PIDs.
- Refer to PID list in Normal Operation to view 2293 fault PIDs.
- Does the original on-demand DTC B2293 fault PID indicate a fault?

Yes
INSTALL a new passenger air bag module. REFER to Passenger Air Bag Module Passenger Air Bag Module. GO to C56.

No
In the process of diagnosing the fault, the fault condition has become intermittent. Using the fault PIDs recorded, GO to the appropriate pinpoint test step and CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of electrical connectors that were disconnected.

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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