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N1-N15




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


Pinpoint Tests


Pinpoint Test N: DTC B2296

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

Lamp Fault Codes (LFCs)

The following LFCs indicate the specific faults associated with DTC B2296:





Normal Operation

The impact sensor(s) provide data to the Restraints Control Module (RCM) for use in calculating impact severity. This is accomplished using various electrical and electro-mechanical sensor(s) throughout the vehicle.

The RCM checks all of the impact sensor circuits for faults. If the RCM detects one of the following faults on any of the impact sensor circuits, it will store DTC B2296 in memory and, depending on the fault, flash a LFC on the air bag warning indicator.





a Fault PIDs that end in OD indicate an on-demand status and are associated with on-demand DTC B2296. Fault PIDs that end in CM indicate continuous memory status and are associated with continuous DTC B2296.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Impact sensor
- Incorrect sensor mounting
- RCM



PINPOINT TEST N: DTC B2296

WARNING: Remove restraint system diagnostic tools from the vehicle prior to road testing. If tools are not removed, the supplemental restraint system (SRS) device may not deploy in a crash. Failure to follow this instruction may result in serious personal injury or death in a crash and possibly violate vehicle safety standards.

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 safety belt buckle/retractor pretensioners or adaptive load limiting retractors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors, 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: The Supplemental Restraint System (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.

NOTE: 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.

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N1 CHECK FOR ON-DEMAND AND CONTINUOUS 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 B2296 Fault PIDs.
- Refer to PID list in Normal Operation to view B2296 fault PIDs.
- Do any on-demand B2296 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 2296_31_OD (Side Crash Sensor Mount or Communication Fault, Front Driver Side) (LFC 4-12), GO to N2.

For 2296_17_OD (Side Crash Sensor Communication Fault, Front Driver Side) (LFC 4-3), GO to N8.

For 2296_30_OD (Side Crash Sensor Internal Fault, Front Driver Side) (LFC 6-2), INSTALL a new driver side impact sensor. REFER to Side Impact Sensor Side Impact Sensor. GO to N44.

For 2296_16_OD (Side Crash Sensor Circuit Short to Ground, Front Driver Side) (LFC 6-7), GO to N7.

For 2296_15_OD (Side Crash Sensor Circuit Short to Battery, Front Driver Side) (LFC 6-12), GO to N6.

For 2296_29_OD (Side Crash Sensor Mount or Communication Fault, Front Passenger Side) (LFC 4-13), GO to N12.

For 2296_14_OD (Side Crash Sensor Communication Fault, Front Passenger Side) (LFC 4-4), GO to N18.

For 2296_28_OD (Side Crash Sensor Internal Fault, Front Passenger Side) (LFC 6-3), INSTALL a new first row passenger side impact sensor. REFER to Side Impact Sensor Side Impact Sensor. GO to N44.

For 2296_13_OD (Side Crash Sensor Circuit Short to Ground, Front Passenger Side) (LFC 6-8), GO to N17.

For 2296_12_OD (Side Crash Sensor Circuit Short to Battery, Front Passenger Side) (LFC 6-13), GO to N16.

For 2296_19_OD (Driver/Center Front Crash Sensor Mount/Communication Fault) (LFC 4-11), GO to N22.

For 2296_5_OD (Driver/Center Front Crash Sensor Communication Fault) (LFC 4-2), GO to N28.

For 2296_18_OD (Driver/Center Front Crash Sensor Internal Fault) (LFC 6-1), INSTALL a new front impact severity sensor. REFER to Front Impact Severity Sensor Front Impact Severity Sensor. GO to N44.

For 2296_4_OD (Driver/Center Front Crash Sensor Circuit Short to Ground) (LFC 6-6), GO to N27.

For 2296_3_OD (Driver/Center Front Crash Sensor Circuit Short to Battery) (LFC 6-11), GO to N26.

For 2296_59_OD (Passenger Front Crash Sensor Mount or Communication Fault) (LFC 12-2), GO to N32.

For 2296_57_OD (Passenger Front Crash Sensor Communication Fault) (LFC 12-4), GO to N38.

For 2296_58_OD (Passenger Front Crash Sensor Internal Fault) (LFC 12-3), INSTALL a new RH front impact severity sensor. REFER to Front Impact Severity Sensor Front Impact Severity Sensor. GO to N44.

For 2296_56_OD (Passenger Front Crash Sensor Circuit Short to Ground) (LFC 12-5), GO to N37.

For 2296_55_OD (Passenger Front Crash Sensor Circuit Short to Battery) (LFC 12-6), GO to N36.

No
This is an intermittent fault when present as a continuous memory DTC only (DTC not retrieved on demand). The fault condition is not present at this time. GO to N43.

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N2 INSPECT THE DRIVER SIDE IMPACT SENSOR MOUNTING AND MOUNTING SURFACE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Access the driver side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- Inspect the driver side impact sensor for:
- a loose electrical connector.
- a loose sensor mounting bolt.
- Remove the driver side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- Visually inspect the driver side impact sensor, alignment tabs, electrical connector and mounting surface for damage, corrosion or dirt.
- Was a significant amount of corrosion or dirt found, was the driver side impact sensor attached to the mounting surface incorrectly or were the impact sensor bolts not fully seated and tightened correctly?

Yes
CLEAN and TIGHTEN the bolts to the required specification. REPAIR the mounting surface and electrical connections as necessary. REINSTALL the driver side impact sensor. GO to N44.

No
GO to N3.

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N3 INSTALL THE DRIVER SIDE IMPACT SENSOR AND CARRY OUT THE SELF-TEST


- Clean and repair the mounting surface as necessary.
- Clean the driver side impact sensor mounting bolts.
- Install the driver side impact sensor and tighten to the required specification.
- 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.
- 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 B2296 Fault PIDs.
- Refer to PID list in Normal Operation to view B2296 fault PIDs.
- Do any on-demand B2296 fault PIDs indicate a fault?

Yes
GO to N4.

No
Fault corrected. GO to N44.

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N4 CHECK THE DRIVER SIDE IMPACT SENSOR GROUND CIRCUIT 1262 (BN/LG) FOR HIGH RESISTANCE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Driver Side Impact Sensor C305.
- Measure the resistance between driver side impact sensor C305-2, circuit 1262 (BN/LG), harness side and the driver side impact sensor case ground bolt.




- Is the resistance less than 100 ohms?

Yes
GO to N11.

No
GO to N5.

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N5 CLEAN THE DRIVER SIDE IMPACT SENSOR MOUNTING SURFACE AND CARRY OUT THE SELF-TEST


- Remove the driver side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- Clean and repair the mounting surface as necessary.
- Clean the driver side impact sensor mounting bolts.
- Install the driver side impact sensor and tighten to specifications.
- 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.
- 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 B2296 Fault PIDs.
- Refer to PID list in Normal Operation to view B2296 fault PIDs.
- Do any on-demand B2296 fault PIDs indicate a fault?

Yes
GO to N11.

No
Fault corrected. GO to N44.

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N6 CHECK CIRCUITS 1261 (WH/LG) AND 1262 (BN/LG) FOR A SHORT TO VOLTAGE BETWEEN THE DRIVER SIDE IMPACT SENSOR AND RCM


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Driver Side Impact Sensor C305.
- 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 driver side impact sensor:
- C305-2, circuit 1262 (BN/LG), harness side and ground.
- C305-1, circuit 1261 (WH/LG), harness side and ground.




- Is voltage present on either circuit?

Yes
REPAIR circuit 1261 (WH/LG) or 1262 (BN/LG). GO to N44.

No
GO to N11.

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N7 CHECK CIRCUITS 1261 (WH/LG) AND 1262 (BN/LG) FOR A SHORT TO GROUND BETWEEN THE DRIVER SIDE IMPACT SENSOR AND RCM


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Driver Side Impact Sensor C305.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between driver side impact sensor:
- C305-2, circuit 1262 (BN/LG), harness side and ground.
- C305-1, circuit 1261 (WH/LG), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to N11.

No
REPAIR circuit 1261 (WH/LG) or 1262 (BN/LG). GO to N44.

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N8 CHECK CIRCUIT 1261 (WH/LG) FOR AN OPEN BETWEEN THE RCM AND DRIVER SIDE IMPACT SENSOR


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Driver Side Impact Sensor C305.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310b-27, circuit 1261 (WH/LG), harness side and driver side impact sensor C305-1, circuit 1261 (WH/LG), harness side.




- Is the resistance less than 0.5 ohm?

Yes
GO to N9.

No
REPAIR circuit 1261 (WH/LG). GO to N44.

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N9 CHECK CIRCUIT 1262 (BN/LG) FOR AN OPEN BETWEEN THE RCM AND DRIVER SIDE IMPACT SENSOR


- Measure the resistance between RCM C310b-28, circuit 1262 (BN/LG), harness side and driver side impact sensor C305-2, circuit 1262 (BN/LG), harness side.




- Is the resistance less than 0.5 ohm?

Yes
GO to N10.

No
REPAIR circuit 1262 (BN/LG). GO to N44.

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N10 CHECK FOR A SHORT BETWEEN CIRCUITS 1261 (WH/LG) AND 1262 (BN/LG) BETWEEN THE RCM AND DRIVER SIDE IMPACT SENSOR


- Measure the resistance between driver side impact sensor C305-1, circuit 1261 (WH/LG), and C305-2, circuit 1262 (BN/LG), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to N11.

No
REPAIR circuits 1261 (WH/LG) and 1262 (BN/LG). GO to N44.

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N11 CHECK THE DRIVER SIDE IMPACT SENSOR


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Connect: RCM C310a and C310b.
- Install a known good driver side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- 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.
- 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 B2296 Fault PIDs.
- Refer to PID list in Normal Operation to view B2296 fault PIDs.
- Were any on-demand fault PIDs for the driver side impact sensor indicating a fault?

Yes
GO to N42.

No
Fault corrected. GO to N44.

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N12 INSPECT THE PASSENGER SIDE IMPACT SENSOR MOUNTING AND MOUNTING SURFACE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Access the passenger side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- Inspect the passenger side impact sensor for:
- a loose electrical connector.
- a loose sensor mounting bolt.
- Remove the passenger side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- Visually inspect the passenger side impact sensor, alignment tabs, electrical connector and mounting surface for damage, corrosion or dirt.
- Was a significant amount of corrosion or dirt found, was the passenger side impact sensor attached to the mounting surface incorrectly or were the sensor bolts not fully seated and tightened correctly?

Yes
CLEAN and TIGHTEN the bolts to required specifications. REPAIR the mounting surface and electrical connections as necessary. REINSTALL the passenger side impact sensor. GO to N44.

No
GO to N13.

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N13 INSTALL THE PASSENGER SIDE IMPACT SENSOR AND CARRY OUT THE SELF-TEST


- Clean and repair the mounting surface as necessary.
- Clean the passenger side impact sensor mounting bolts.
- Install the passenger side impact sensor and tighten to the required specification.
- 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.
- 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 B2296 Fault PIDs.
- Refer to PID list in Normal Operation to view B2296 fault PIDs.
- Do any on-demand B2296 fault PIDs indicate a fault?

Yes
GO to N14.

No
Fault corrected. GO to N44.

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N14 CHECK THE PASSENGER SIDE IMPACT SENSOR GROUND CIRCUIT 1264 (BN) FOR HIGH RESISTANCE


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Passenger Side Impact Sensor C304.
- Measure the resistance between passenger side impact sensor C304-2, circuit 1264 (BN), harness side and passenger side impact sensor case ground bolt.




- Is the resistance less than 100 ohms?

Yes
GO to N21.

No
GO to N15.

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N15 CLEAN FIRST ROW PASSENGER SIDE IMPACT SENSOR MOUNTING SURFACE AND CARRY OUT THE SELF-TEST


- Remove the passenger side impact sensor. Refer to Side Impact Sensor Side Impact Sensor.
- Clean and repair the mounting surface as necessary.
- Clean the passenger side impact sensor mounting bolts.
- Install the passenger side impact sensor and tighten to the required specification.
- 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.
- 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 B2296 Fault PIDs.
- Refer to PID list in Normal Operation to view B2296 fault PIDs.
- Do any on-demand B2296 fault PIDs indicate a fault?

Yes
GO to N21.

No
Fault corrected. GO to N44.

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