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M1-M14




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

Pinpoint Tests

Pinpoint Test M: LFC 24/25 DTC B2294

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 Safety Canopy(R) 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 B2294 in memory and send a message to the Instrument Cluster (IC) module to flash Lamp Fault Code (LFC) 24 or 25 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 Safety Canopy(R) module circuits for resistance and expects a normal resistance between 1.50 and 3.04 ohms.

If loop 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 B2294. Fault PIDs that end in CM indicate continuous memory status and are associated with continuous DTC B2294.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Safety Canopy(R) module
- RCM

PINPOINT TEST M: LFC 24/25 DTC B2294

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.

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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M1 RETRIEVE RCM DTCs


- 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 2294 Fault PIDs.
- Refer to PID list in Normal Operation to view 2294 fault PIDs.
- Do any on-demand 2294 fault PIDs indicate a fault?

Yes
This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test.

Using the on-demand fault PIDs recorded, GO to the appropriate pinpoint test step.

For 2294_28_OD, GO to M2.

For 2294_29_OD, GO to M2.

For 2294_30_OD, GO to M9.

For 2294_31_OD, GO to M11.

For 2294_24_OD, GO to M12.

For 2294_25_OD, GO to M12.

For 2294_26_OD, GO to M19.

For 2294_27_OD, GO to M21.

No
This is an intermittent fault when present as a CMDTC.

Using the fault PIDs recorded, GO to the appropriate pinpoint test step.

For 2294_28_CM, 2294_24_CM, 2294_29_CM or 2294_25_CM, GO to M24.

For 2294_30_CM or 2294_26_CM, GO to M26.

For 2294_31_CM or 2294_27_CM, GO to M27.

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M2 CHECK THE DRIVER SAFETY CANOPY MODULE RESISTANCE (D_CURTL1) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM .
- Enter the following diagnostic mode on the scan tool: DCURTL1 Resistance PID.
- Does the PID value read between 1.50 and 3.04 ohms?

Yes
GO to M23.

No
GO to M3.

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M3 CHECK THE DRIVER SAFETY CANOPY MODULE RESISTANCE (D_CURTL1) PID WHILE CARRYING OUT A HARNESS TEST


- While monitoring the DCURTL1 PID while carry out a harness test of the driver safety canopy circuits and accessible connectors (including any in-line connectors) by wiggling connectors and flexing the wire harness.
- Does the PID value read between 1.50 and 3.04 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 M28.

No
If the DCURTL1 PID is less than 1.50 ohms, GO to M4.

If the DCURTL1 PID is greater than 3.04 ohms, GO to M7.

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M4 CHECK THE DRIVER SAFETY CANOPY FOR FAULT PID 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: Driver Safety Canopy(R) C9018.
- 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 .
- 2294_28_OD
- 2294_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2294 on-demand fault PIDs with the driver Safety Canopy(R) module disconnected, an open circuit fault would normally be retrieved.
- Did the driver Safety Canopy on-demand fault PID change from a low resistance to an open circuit fault?

Yes
GO to M22.

No
GO to M5.

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M5 CHECK FOR A SHORT BETWEEN DRIVER SAFETY CANOPY 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 driver Safety Canopy(R) C9018-2, circuit CR109 (BN/BU), harness side and C9018-1, circuit RR109 (BU/GN), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to M23.

No
GO to M6.

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M6 CHECK THE RCM FOR LOW RESISTANCE


- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310b pin 21, component side, and C310b pin 22, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR109 (BN/BU) and RR109 (BU/GN). GO to M28.

No
GO to M23.

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M7 CHECK THE DRIVER SAFETY CANOPY(R) MODULE 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: Driver Safety Canopy C9018.
- Connect a fused jumper wire between driver safety canopy C9018-2, circuit CR109 (BN/BU), harness side and C9018-1, circuit RR109 (BU/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.
- 2294_28_OD
- 2294_29_OD
- DIAGNOSTIC TIP: When viewing DTC B2294 on-demand fault PIDs with the driver safety canopy circuits shorted together, a low resistance fault would normally be retrieved.
- Did the driver safety canopy on-demand fault PID change from an open circuit to a low resistance fault?

Yes
GO to M22.

No
GO to M8.

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M8 CHECK THE DRIVER SAFETY CANOPY MODULE 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 driver safety canopy electrical connector.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310b, harness side and driver safety canopy C9018, harness side using the following chart.









- Are the resistances less than 0.5 ohm?

Yes
GO to M23.

No
REPAIR circuit CR109 (BN/BU) or RR109 (BU/GN). GO to M28.

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M9 CHECK THE DRIVER SAFETY CANOPY MODULE FAULT PID FOR A FAULT 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: Driver Safety Canopy C9018.
- 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.
- 2294_29_OD
- 2294_30_OD
- DIAGNOSTIC TIP: When viewing DTC B2294 on-demand fault PIDs with the driver safety canopy disconnected, an open circuit fault would normally be retrieved.
- Did the driver safety canopy on-demand PID change from a short to ground to an open circuit fault?

Yes
GO to M22.

No
GO to M10.

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M10 CHECK THE DRIVER SAFETY CANOPY MODULE 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 driver safety canopy:
- C9018-2, circuit CR109 (BN/BU), harness side and ground.
- C9018-1, circuit RR109 (BU/GN), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to M23.

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 CR109 (BN/BU) or RR109 (BU/GN). GO to M28.

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M11 CHECK THE DRIVER SAFETY CANOPY MODULE 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: Driver Safety Canopy C9018.
- 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 safety canopy:
- C9018-2, circuit CR109 (BN/BU), harness side and ground.
- C9018-1, circuit RR109 (BU/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 CR109 (BN/BU) or RR109 (BU/GN). GO to M28.

No
GO to M23.

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M12 CHECK THE PASSENGER SAFETY CANOPY MODULE RESISTANCE (P_CURTL1) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM .
- Enter the following diagnostic mode on the scan tool: PCURTL1 PID.
- Does PID value read between 1.50 and 3.04 ohms?

Yes
GO to M23.

No
GO to M13.

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M13 CHECK THE PASSENGER SAFETY CANOPY MODULE RESISTANCE (P_CURTL1) PID WHILE CARRYING OUT A HARNESS TEST


- Continue monitoring the PCURTL1 resistance PID while carrying out a harness test of the passenger safety canopy circuits and accessible connectors (including any in-line connectors), by wiggling connectors and flexing the wire harness.
- Does the PID value read between 1.50 and 3.04 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 M28.

No
If the PCURTL1 PID is less than 1.50 ohms, GO to M14.

If the PCURTL1 PID is greater than 3.04 ohms, GO to M17.

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M14 CHECK THE PASSENGER SAFETY CANOPY MODULE FAULT PID FOR A FAULT 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 Safety Canopy C9019.
- 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 .
- 2294_24_OD
- 2294_25_OD
- DIAGNOSTIC TIP: When viewing DTC B2294 on-demand fault PIDs with the passenger safety canopy disconnected, an open circuit fault would normally be retrieved.
- Did the passenger safety canopy on-demand PID change from a low resistance to an open circuit fault?

Yes
GO to M22.

No
GO to M15.

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