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Home >> Lincoln >> 2009 >> MKS AWD V6-3.7L >> Repair and Diagnosis >> Restraints and Safety Systems >> Air Bag Systems >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Test N: LFC 22/23 DTC B2295 >> N15-N28

N15-N28




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

Pinpoint Tests

Pinpoint Test N: LFC 22/23 DTC B2295

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 seat side air bag circuits for the following faults:

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

If a fault is detected, the RCM will store DTC B2295 in memory and send a message to the Instrument Cluster (IC) module to flash a Lamp Fault Code (LFC) 22 or 23 on the air bag warning indicator. After the LFCs are displayed, the air bag warning indicator will remain illuminated for the rest of the ignition cycle.

The RCM monitors seat side air bag circuits for resistance and expects a normal resistance between 1.50 and 3.04 ohms.

If resistance is between 1.04 and 1.50 ohms or between 3.04 and 3.72 ohms, there exists a strong potential for a fault to occur (a DTC may or may not set). The RCM will set 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 on-demand DTC B2295. Fault PIDs that end in CM indicate continuous memory status and are associated with continuous DTC B2295.

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

PINPOINT TEST N: LFC 22/23 DTC B2295

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.

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 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.

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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N15 CHECK FOR A SHORT BETWEEN PASSENGER SEAT SIDE AIR BAG MODULE CIRCUITS


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Measure the resistance between passenger seat side air bag module C3133-1, circuit CR106 (VT/GY), harness side and C3133-2, circuit RR106 (YE/OG), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to N23.

No
GO to N16.

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N16 CHECK THE RCM FOR LOW RESISTANCE


- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310b pins 9 and 10, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR106 (VT/GY) and RR106 (YE/OG). GO to N28.

No
GO to N23.

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N17 CHECK THE PASSENGER SIDE AIR BAG FAULT PID FOR A 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 Seat Side Air Bag C3133.
- Connect a fused jumper wire between passenger seat side air bag C3133-1, circuit CR106 (VT/GY), harness side and C3133-2, circuit RR106 (YE/OG), 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 .
- 2295_24_OD
- 2295_25_OD
- DIAGNOSTIC TIP: When viewing DTC B2295 on-demand fault PIDs with the passenger seat side air bag circuits shorted together, a low resistance fault would normally be retrieved.
- Did the passenger seat side air bag on-demand PID change from indicating an open circuit to a low resistance fault?

Yes
GO to N22.

No
GO to N18.

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N18 CHECK THE PASSENGER SEAT SIDE AIR BAG 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 fused jumper wire from the passenger seat side air bag C3133.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310b, harness side and passenger seat side air bag module C3133, harness side using the following chart.









- Are the resistances less than 0.5 ohm?

Yes
GO to N23.

No
REPAIR circuit CR106 (VT/GY) or RR106 (YE/OG). GO to N28.

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N19 CHECK THE PASSENGER SEAT SIDE AIR BAG MODULE 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.
- Disconnect: Passenger Seat Side Air Bag Module C3133.
- 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.
- 2295_25_OD
- 2295_26_OD
- DIAGNOSTIC TIP: When viewing DTC B2295 on-demand fault PIDs with the passenger seat side air bag disconnected, an open circuit fault would normally be retrieved.
- Did the passenger seat side air bag on-demand PID change from indicating a short to ground to an open circuit fault?

Yes
GO to N22.

No
GO to N20.

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N20 CHECK THE PASSENGER SEAT SIDE AIR BAG 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 passenger seat side air bag:
- C3133-1, circuit CR106 (VT/GY), harness side and ground.
- C3133-2, circuit RR106 (YE/OG), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to N23.

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 CR106 (VT/GY) or RR106 (YE/OG). GO to N28.

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N21 CHECK THE PASSENGER SEAT SIDE AIR BAG 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 Seat Side Air Bag Module C3133.
- Disconnect: Passenger Safety Belt Buckle Pretensioner Electrical Connector.
- 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 passenger seat side air bag:
- C3133-1, circuit CR106 (VT/GY), harness side and ground.
- C3133-2, circuit RR106 (YE/OG), 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 CR106 (VT/GY) or RR106 (YE/OG). GO to N28.

No
GO to N23.

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N22 CONFIRM THE SEAT SIDE AIR BAG MODULE FAULT


NOTE: Make sure all restraint system components, sensor electrical connectors 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: Affected Side Air Bag C3134 (Driver) C3133 (Passenger).
- Connect: 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.
- 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 2295 Fault PIDs.
- Refer to PID list in Normal Operation to view 2295 fault PIDs.
- Does the original on-demand 2295 fault PID indicate a fault?

Yes
REMOVE and INSPECT the seat side air bag harness, connector terminals for damage. REFER to Side Air Bag Module Side Air Bag Module. GO to N28.

If a concern was not found, INSTALL a new driver or passenger seat side air bag module. GO to N28.

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.

For 2295_28_CM, 2295_24_CM, 2295_29_CM or 2295_25_CM, GO to N24.

For 2295_30_CM or 2295_26_CM, GO to N26.

For 2295_31_CM or 2295_27_CM, GO to N27.

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N23 CONFIRM THE RCM FAULT


NOTE: Make sure all restraint system components, sensor electrical connectors 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.
- Prior to reconnecting any previously disconnected SRS component:
- inspect connector(s) (including any in-line connectors) for pushed out, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- inspect C310a and C310b connector position assurance lever/lock for correct operation. Refer to Restraints Control Module (RCM) Service and Repair.
- repair any concerns found. Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number

- If previously directed to disconnect any SRS component(s):
- depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- connect all previously disconnected restraint system component(s), including 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.
- 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 2295 Fault PIDs.
- Refer to PID list in Normal Operation to view 2295 fault PIDs.
- Does the original on-demand 2295 fault PID indicate a fault?

Yes
INSTALL a new RCM and CARRY OUT Programmable Module Installation (PMI). REFER to Restraints Control Module (RCM) Service and Repair. GO to N28. Programming and Relearning

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.

For 2295_28_CM, 2295_24_CM, 2295_29_CM or 2295_25_CM, GO to N24.

For 2295_30_CM or 2295_26_CM, GO to N26.

For 2295_31_CM or 2295_27_CM, GO to N27.

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N24 CHECK THE SIDE AIR BAG FAULT PIDs FOR AN INTERMITTENT LOW RESISTANCE OR OPEN


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - View and Record All 2295 Fault PIDs.
- Refer to PID list in Normal Operation to view 2295 fault PIDs.
- If the fault was reported for the driver seat side air bag, monitor the DS_AB PID on the scan tool.
- If the fault was reported for the passenger seat side air bag, monitor the PS_AB PID on the scan tool.
- NOTE: A resistance PID that reads between 1.36 and 1.50 ohms or between 3.04 and 3.72 ohms may or may not set a DTC yet indicates a strong potential for a fault to occur. Make sure to thoroughly check wire harness(es), connectors and terminals as they are the likely source of the fault condition.
- Attempt to recreate the fault by wiggling connectors (including any in-line connectors) and flexing the wire harness.
- Does any on-demand 2295 PID indicate a fault is present or is the seat side air bag PID less than 1.50 ohms or greater than 3.04 ohms?

Yes
DEPOWER the SRS and REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to N28.

No
GO to N25.

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N25 CHECK HARNESS AND CONNECTORS


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect the affected seat side air bag module C3134 (driver) C3133 (passenger):
- inspect connector(s) (including any in-line connectors) for corrosion, loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- Were any concerns found?

Yes
REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to N28.

No
The fault is not present and cannot be recreated at this time. GO to N28.

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N26 CHECK THE SIDE AIR BAG MODULE FAULT PIDs FOR AN INTERMITTENT SHORT TO GROUND


- If the fault was reported for the driver seat side air bag, monitor the driver seat side air bag short to ground on-demand PID 2295_30_OD on the scan tool.
- If the fault was reported for the passenger seat side air bag, monitor the passenger seat side air bag short to ground on-demand PID 2295_26_OD on the scan tool.
- Attempt to recreate the fault by wiggling connectors (including any in-line connectors) and flexing the wire harness.
- Does any on-demand 2295 PID indicate a fault is present?

Yes
DEPOWER the SRS and REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to N28.

No
The fault is not present and cannot be recreated at this time. GO to N28.

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N27 CHECK THE SIDE AIR BAG MODULE FAULT PIDs FOR AN INTERMITTENT 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 the affected seat side air bag module C3134 (driver) C3133 (passenger).
- 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.
- Monitor the driver or passenger seat side air bag short to battery on-demand PIDs (2295_31_OD or 2295_27_OD) on the scan tool.
- Attempt to recreate the fault by wiggling connectors (including any in-line connectors) and flexing the wire harness.
- Does any on-demand 2295 PID indicate a fault is present?

Yes
DEPOWER the SRS and REPAIR as necessary.

Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to N28.

No
The fault is not present and cannot be recreated at this time. GO to N28.

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N28 CHECK FOR ADDITIONAL SRS DTCs


- Ignition OFF.
- WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
- Reconnect all SRS components (if previously disconnected).
- If previously directed to depower the SRS, repower the SRS. Do notprove 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 - Restraints.
- NOTE: When selecting Restraints from the Self Test menu, DTCs will be retrieved from the RCM and OCSM.
- Are any RCM and/or OCSM DTCs retrieved on-demand during self-test?

Yes
Do not clear any DTCs until all DTCs have been resolved. GO to the DTC Charts for pinpoint test direction. [1][2]Diagnostic Trouble Code Descriptions

No
CLEAR all RCM and OCSM CMDTCs. PROVE OUT the SRS. Repair is complete. RETURN the vehicle to the customer.

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