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Pinpoint Test N21-N31




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

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 disassemble or tamper with safety belt buckle/retractor pretensioners or adaptive load limiting retractors or probe the electrical connectors. 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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N21 CHECK THE PASSENGER 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 passenger 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 the for passenger side impact sensor indicating a fault?

Yes
GO to N42.

No
Fault corrected. GO to N44.

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N22 INSPECT THE LH FRONT IMPACT SEVERITY 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 LH front impact severity sensor. Refer to Front Impact Severity Sensor Front Impact Severity Sensor.
- Inspect the LH front impact severity sensor for:

- a loose electrical connector.
- a loose sensor mounting nut.
- Remove the LH front impact severity sensor. Refer to Front Impact Severity Sensor Front Impact Severity Sensor.
- Visually inspect the LH front impact severity sensor, alignment tabs, electrical connector and mounting surface for damage, corrosion or dirt.
- Was a significant amount of corrosion or dirt found, was the LH front severity impact sensor attached to the mounting surface incorrectly or were the sensor bolts not fully seated and tightened correctly?

Yes
CLEAN and TIGHTEN bolts to the required specification or REPAIR the mounting surface as necessary. REINSTALL the LH front impact severity sensor. GO to N44.

No
GO to N23.

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N23 INSTALL THE LH FRONT IMPACT SEVERITY SENSOR AND CARRY OUT THE SELF-TEST


- Clean and repair the mounting surface as necessary.
- Clean the LH front impact severity sensor mounting bolts.
- Install the LH front impact severity sensor. Refer to Front Impact Severity Sensor Front Impact Severity 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.
- Do any on-demand B2296 fault PIDs indicate a fault?

Yes
GO to N24.

No
Fault corrected. GO to N44.

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N24 CHECK THE LH FRONT IMPACT SEVERITY SENSOR GROUND CIRCUIT 618 (VT/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: LH Front Impact Severity Sensor C1465.
- Measure the resistance between the LH front impact severity sensor C1465-2, circuit 618 (VT/LG), harness side and driver front impact severity sensor case ground.
- Is the resistance less than 100 ohms?

Yes
GO to N31.

No
GO to N25.

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N25 CLEAN THE LH FRONT IMPACT SEVERITY SENSOR MOUNTING SURFACE AND CARRY OUT THE SELF-TEST


- Remove the LH front impact severity sensor. Refer to Front Impact Severity Sensor Front Impact Severity Sensor.
- Clean and repair the mounting surface as necessary.
- Clean the LH front impact severity sensor mounting bolts.
- Install the LH front impact severity sensor. Refer to Front Impact Severity Sensor Front Impact Severity 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.
- Do any on-demand B2296 fault PIDs indicate a fault?

Yes
GO to N31.

No
Fault corrected. GO to N44.

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N26 CHECK CIRCUITS 617 (PK/OG) AND 618 (VT/LG) FOR A SHORT TO VOLTAGE BETWEEN THE RCM AND LH FRONT IMPACT SEVERITY SENSOR


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: LH Front Impact Severity Sensor C1465.
- 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 LH front impact severity sensor:
- C1465-1, circuit 617 (PK/OG), harness side and ground.
- C1465-2, circuit 618 (VT/LG), harness side and ground.




- Is voltage present on either circuit?

Yes
REPAIR circuit 617 (PK/OG) or 618 (VT/LG). GO to N44.

No
GO to N31.

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N27 CHECK CIRCUITS 617 (PK/OG) AND 618 (VT/LG) FOR A SHORT TO GROUND BETWEEN THE RCM AND LH FRONT IMPACT SEVERITY SENSOR


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: LH Front Impact Severity Sensor C1465.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between LH front impact severity sensor:
- C1465-1, circuit 617 (PK/OG), harness side and ground.
- C1465-2, circuit 618 (VT/LG), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to N31.

No
REPAIR circuits 617 (PK/OG) or 618 (VT/LG). GO to N44.

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N28 CHECK CIRCUIT 617 (PK/OG) FOR AN OPEN BETWEEN THE RCM AND LH FRONT IMPACT SEVERITY SENSOR


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: LH Front Impact Severity Sensor C1465.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310b-19, circuit 617 (PK/OG), harness side and LH front impact severity sensor C1465-1, circuit 617 (PK/OG), harness side.




- Is the resistance less than 0.5 ohm?

Yes
GO to N29.

No
REPAIR circuit 617 (PK/OG). GO to N44.

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N29 CHECK CIRCUIT 618 (VT/LG) FOR AN OPEN BETWEEN THE RCM AND LH FRONT IMPACT SEVERITY SENSOR


- Measure the resistance between RCM C310b-20, circuit 618 (VT/LG), harness side and LH front impact severity sensor C1465-2, circuit 618 (VT/LG), harness side.




- Is the resistance less than 0.5 ohm?

Yes
GO to N30.

No
REPAIR circuit 618 (VT/LG). GO to N44.

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N30 CHECK FOR A SHORT BETWEEN CIRCUITS 617 (PK/OG) AND 618 (VT/LG) BETWEEN THE RCM AND LH FRONT IMPACT SEVERITY SENSOR


- Measure the resistance between LH front impact severity sensor C1465-1, circuit 617 (PK/OG), harness side and LH front impact severity sensor C1465-2, circuit 618 (VT/LG), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to N31.

No
REPAIR circuits 617 (PK/OG) and 618 (VT/LG). GO to N44.

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N31 CHECK THE LH FRONT IMPACT SEVERITY 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 LH front impact severity sensor. Refer to Front Impact Severity Sensor Front Impact Severity 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 LH front impact severity sensor indicating a fault?

Yes
GO to N42.

No
Fault corrected. GO to N44.

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