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Home >> Lincoln >> 2009 >> Town Car V8-4.6L Flex Fuel >> Repair and Diagnosis >> Restraints and Safety Systems >> Air Bag Systems >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Test L: DTC B2293 >> L31-L39

L31-L39




L31 CHECK PASSENGER AIR BAG MODULE LOOP 2 CIRCUITS 1518 (BK/WH) AND 1519 (LG/RD) 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: Passenger Air Bag Module Loop 2 Restraint System Diagnostic Service Tool 418-F088.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM:
- C310a-13, circuit 1518 (BK/WH), harness side and ground.
- C310a-14, circuit 1519 (LG/RD), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to L37.

No
Due to the shorting bar feature in the electrical connector, the fault can exist in either circuit. Do not remove or defeat the shorting bar.

REPAIR circuit 1518 (BK/WH) or 1519 (LG/RD). GO to L39.

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L32 CHECK PASSENGER AIR BAG MODULE LOOP 2 CIRCUITS 1518 (BK/WH) AND 1519 (LG/RD) 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 Loop 2 Restraint System Diagnostic Service Tool.
- 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 air bag module:
- loop 2 electrical connector, circuit 1518 (BK/WH), harness side and ground.
- loop 2 electrical connector, circuit 1519 (LG/RD), harness side and ground.




- Is voltage present on either circuit?

Yes
Due to the shorting bar feature in the electrical connector, the fault can exist in either circuit. Do not remove or defeat the shorting bar.

REPAIR circuit 1518 (BK/WH) or 1519 (LG/RD). GO to L39.

No
GO to L37.

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L33 CHECK CIRCUIT 1518 (BK/WH) FOR AN OPEN BETWEEN THE RCM AND PASSENGER AIR BAG MODULE LOOP 2


- 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 Loop 2 Restraint System Diagnostic Service Tool.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310a-13, circuit 1518 (BK/WH), harness side and passenger air bag module loop 2 electrical connector, circuit 1518 (BK/WH), harness side.




- Is the resistance less than 0.5 ohm?

Yes
GO to L34.

No
REPAIR circuit 1518 (BK/WH). GO to L39.

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L34 CHECK CIRCUIT 1519 (LG/RD) FOR AN OPEN BETWEEN THE RCM AND PASSENGER AIR BAG MODULE LOOP 2


- Measure the resistance between RCM C310a-14, circuit 1519 (LG/RD), harness side and passenger air bag module loop 2 electrical connector, circuit 1519 (LG/RD), harness side.




- Is the resistance less than 0.5 ohm?

Yes
GO to L37.

No
REPAIR circuit 1519 (LG/RD). GO to L39.

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L35 CHECK FOR A SHORT BETWEEN PASSENGER AIR BAG MODULE LOOP 2 CIRCUITS 1518 (BK/WH) AND 1519 (LG/RD)


- 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 Restraint System Diagnostic Service Tool.
- Measure the resistance between passenger air bag module loop 2 electrical connector, circuit 1518 (BK/WH), harness side and circuit 1519 (LG/RD), harness side.




- Is the resistance less than 800 ohms?

Yes
GO to L36.

No
GO to L37.

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L36 CHECK THE RCM FOR LOW RESISTANCE


- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310a pin 13, component side and pin 14, component side.




- Is the resistance less than 800 ohms?

Yes
GO to L37.

No
REPAIR circuits 1518 (BK/WH) and 1519 (LG/RD). GO to L39.

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L37 CONFIRM THE RCM FAULT


NOTE: Make sure all Restraint System Diagnostic Service Tools, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the 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: Restraint System Diagnostic Service Tools.
- 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.
- 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 B2293 Fault PIDs.
- Refer to PID list in Normal Operation to view B2293 fault PIDs.
- Do any on-demand DTC B2293 fault PIDs indicate a fault?

Yes
INSTALL a new RCM. REFER to Restraints Control Module (RCM) Service and Repair. GO to L39.

No
In the process of diagnosing the fault, the fault condition has become intermittent. CHECK for causes of the intermittent fault in the areas previously worked in, particularly the pins and terminals of electrical connectors that were disconnected. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. REPAIR any intermittent wiring, terminal or connector concerns found. GO to L39.

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L38 CHECK FOR AN INTERMITTENT FAULT


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- If the fault PID was reported for the driver air bag module:
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Connect Restraint System Diagnostic Service Tools 418-F395 (2 required) to the driver air bag module loop 1 and loop 2 connectors.
- NOTE: Detach and disconnect the passenger air bag module jumper harness and connect the Restraint System Diagnostic Service Tools, refer to Supplemental Restraint System (SRS) Deactivation and Reactivation Supplemental Restraint System (SRS) Deactivation and Reactivation.
- If the fault PID was reported for the passenger air bag module:
- Remove the passenger air bag module. Refer to Passenger Air Bag Module Passenger Air Bag Module.
- Remove the passenger air bag module jumper harness from the passenger air bag module.
- Connect Restraint System Diagnostic Service Tools 418-F395 (2 required) to the passenger air bag module jumper harness electrical connectors.
- Connect the passenger air bag module jumper harness with Restraint System Diagnostic Service Tools to 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.
- 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 B2293 Fault PIDs.
- Refer to PID list in Normal Operation to view B2293 fault PIDs.
- Do any on-demand DTC B2293 fault PIDs indicate a fault?

Yes
The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self-test. CHECK for causes of the intermittent fault at or near the affected air bag module connector. REPAIR any intermittent wiring, terminals or connector concerns found.

If an intermittent concern was found and repaired, GO to L39.

If an intermittent concern was not found and repaired, USE the fault PIDs recorded and GO to the appropriate pinpoint test step.

For 2293_31_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side) (LFC 8-3), GO to L3.

For 2293_30_OD (Air Bag Circuit Short to Battery - Loop No. 1, Front Driver Side) (LFC 8-7), GO to L5.

For 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side) (LFC 1-9), GO to L7.

For 2293_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side) (LFC 8-11), GO to L11.

For 2293_27_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side) (LFC 8-5), GO to L14.

For 2293_26_OD (Air Bag Circuit Short to Battery - Loop No. 1, Front Passenger Side) (LFC 8-9), GO to L15.

For 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side) (LFC 2-1), GO to L16.

For 2293_24_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side) (LFC 8-13), GO to L18.

For 2293_23_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Driver Side) (LFC 8-4), GO to L20.

For 2293_22_OD (Air Bag Circuit Short to Battery - Loop No. 2, Front Driver Side) (LFC 8-8), GO to L22.

For 2293_21_OD (Air Bag Circuit Open - Loop No. 2, Front Driver Side) (LFC 8-1), GO to L24.

For 2293_20_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Driver Side) (LFC 8-12), GO to L28.

For 2293_19_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side) (LFC 8-6), GO to L31.

For 2293_18_OD (Air Bag Circuit Short to Battery - Loop No. 2, Front Passenger Side) (LFC 8-10), GO to L32.

For 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side) (LFC 8-2), GO to L33.

For (2293_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side) (LFC 8-14), GO to L35.

No
CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test. REPAIR any intermittent wiring, terminals or connector concerns found. GO to L39.

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L39 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 - RCM.
- Are any RCM 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 continuous memory DTCs. PROVE OUT the SRS. Repair is complete. RETURN the vehicle to the customer.

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