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Home >> Mercury >> 2009 >> Milan AWD L4-2.3L >> Repair and Diagnosis >> Restraints and Safety Systems >> Air Bag Systems >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Tests - Restraints Control Module (RCM) >> Pinpoint Test H: DTC B2295 >> H1-H14

H1-H14




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

Pinpoint Tests - Restraints Control Module (RCM)

Pinpoint Test H: 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 side air bag module circuits (loop) for an acceptable resistance range, unacceptable voltage and shorts to ground. The RCM will store DTC B2294 in memory if any of these conditions are detected. If the RCM detects a fault, it will send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

As the RCM continuously monitors side air bag module circuits for resistance, it expects a normal resistance between 1.31 to 4.29 ohms.

If a loop resistance is between 0.9 and 1.31 or between 4.29 and 5 ohms, there exists a strong potential for an intermittent fault, a DTC may or may not set. The RCM will also set an on-demand DTC if the loop resistance is less than 0.9 ohm or greater than 5 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 H: DTC B2295

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: Supplemental Restraint System (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.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.

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H1 RETRIEVE RCM 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 2295 Fault PIDs.
- Refer to PID list in Normal Operation to view 2295 fault PIDs.
- Do any on-demand B2295 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 2295_28_OD (Side Air Bag Circuit Resistance Low, Front Driver Side), GO to H2.

For (2295_29_OD (Side Air Bag Circuit Open, Front Driver Side), GO to H2.

For 2295_30_OD (Side Air Bag Circuit Short to Ground, Front Driver Side), GO to H9.

For 2295_31_OD (Side Air Bag Circuit Short to Battery, Front Driver Side), GO to H11.
For 2295_24_OD (Side Air Bag Circuit Resistance Low, Front Passenger Side), GO to H12.

For 2295_25_OD (Side Air Bag Circuit Open, Front Passenger Side), GO to H12.

For 2295_26_OD (Side Air Bag Circuit Short to Ground, Front Passenger Side), GO to H19.

For (2295_27_OD (Side Air Bag Circuit Short to Battery, Front Passenger Side), GO to H21.

No
This is an intermittent fault when present as a Continuous Memory Diagnostic Trouble Code (CMDTC). The fault condition is not present at this time.

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

For 2295_28_CM (Side Air Bag Circuit Resistance Low, Front Driver Side), 2295_29_CM (Side Air Bag Circuit Open, Front Driver Side), 2295_24_CM (Side Air Bag Circuit Resistance Low, Front Passenger Side) or 2295_25_CM (Side Air Bag Circuit Open, Front Passenger Side), GO to H24.

For (2295_30_CM (Side Air Bag Circuit Short to Ground, Front Driver Side) or 2295_26_CM (Side Air Bag Circuit Short to Ground, Front Passenger Side), GO to H26.

For 2295_31_CM (Side Air Bag Circuit Short to Battery, Front Driver Side) or 2295_27_CM (Side Air Bag Circuit Short to Battery, Front Passenger Side), GO to H27.

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H2 CHECK DRIVER SIDE AIR BAG MODULE RESISTANCE (DS_AB) PID


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM .
- Enter the following diagnostic mode on the scan tool: DS_AB PID.
- Does the resistance PID value read between 1.31 and 4.29 ohms?

Yes
GO to H23.

No
GO to H3.

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H3 CHECK DRIVER SIDE AIR BAG RESISTANCE (DS_AB) PID WHILE CARRYING OUT A HARNESS TEST


- Continue monitoring the DS_AB PID while carrying out a harness test of the driver side air bag circuits and accessible connectors (including any inline connectors) by wiggling connectors and flexing the wire harness.
- Does the resistance PID value read between 1.31 and 4.29 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 H28.

No
If the DS_AB PID is less than 1.31 ohms, GO to H4.

If the DS_AB PID is greater than 4.29 ohms, GO to H7.

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H4 CHECK DRIVER SIDE AIR BAG MODULE FAULT PIDs FOR A 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 Side Air Bag Module C328.
- 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_28_OD (Side Air Bag Circuit Resistance Low, Front Driver Side)
- 2295_29_OD (Side Air Bag Circuit Open, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2295 on-demand fault PIDs with the driver side air bag disconnected, an open circuit fault would normally be retrieved.
- Did the on-demand fault PID change from a low resistance to an open circuit fault?

Yes
GO to H22.

No
GO to H5.

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H5 CHECK FOR A SHORT BETWEEN DRIVER SEAT SIDE AIR BAG CIRCUITS


- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Measure resistance between driver side air bag C328-2, circuit CR105 (GN/BU), harness side and C328-1, circuit RR105 (GY/YE), harness side.




- Is the resistance greater than 10,000 ohms?

Yes
GO to H22.

No
GO to H6.

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H6 CHECK RCM FOR LOW RESISTANCE


- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310b pin 7, component side, and C310b pin 8, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR105 (GN/BU) and RR105 (GY/YE). GO to H25.

No
GO to H23.

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H7 CHECK DRIVER SIDE AIR BAG MODULE FAULT PIDs FOR A 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 Side Air Bag Module C328.
- Connect a jumper wire between driver side air bag C328-2, circuit CR105 (GN/BU), harness side and C328-1, circuit RR105 (GY/YE), 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_28_OD (Side Air Bag Circuit Resistance Low, Front Driver Side)
- 2295_29_OD (Side Air Bag Circuit Open, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2295 on-demand fault PIDs with the driver side air bag module circuits shorted together, a low resistance fault would normally be retrieved.
- Did the on-demand fault PID change from an open circuit to a low resistance fault?

Yes
GO to H22.

No
GO to H8.

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H8 CHECK DRIVER SIDE AIR BAG 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 jumper wire from the driver side air bag C328.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310b, harness side and driver seat side air bag C328, harness side using the following chart.









- Are the resistances less than 0.5 ohm?

Yes
GO to H23.

No
REPAIR circuit CR105 (GN/BU) or RR105 (GY/YE). GO to H28.

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H9 CHECK DRIVER SIDE AIR BAG MODULE FAULT PIDs FOR A 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 Side Air Bag Module C328.
- 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_29_OD (Side Air Bag Circuit Open, Front Driver Side)
- 2295_30_OD (Side Air Bag Circuit Short to Ground, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2295 on-demand fault PIDs with the driver side air bag module disconnected, an open circuit fault would normally be retrieved.
- Did the on-demand fault PID change from a short to ground to an open circuit fault?

Yes
GO to H22.

No
GO to H10.

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H10 CHECK DRIVER SIDE AIR BAG 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 resistance between:
- driver side air bag C328-2, circuit CR105 (GN/BU), harness side and ground.
- driver side air bag C328-1, circuit RR105 (GY/YE), harness side and ground.




- Is the resistance greater than 10,000 ohms?

Yes
GO to H23.

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 CR105 (GN/BU) or RR105 (GY/YE). GO to H28.

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H11 CHECK DRIVER SIDE AIR BAG 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 Side Air Bag Module C328.
- 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 voltage between:
- driver side air bag C328-2, circuit CR105 (GN/BU), harness side and ground.
- driver side air bag C328-1, circuit RR105 (GY/YE), 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 CR105 (GN/BU) or RR105 (GY/YE). GO to H28.

No
GO to H23.

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H12 CHECK PASSENGER SIDE AIR BAG MODULE RESISTANCE (PS_AB) PID


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - RCM .
- Enter the following diagnostic mode on the scan tool: PS_AB PID.
- Does the resistance PID value read between 1.31 and 4.29 ohms?

Yes
GO to H23.

No
GO to H13.

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H13 CHECK PASSENGER SIDE AIR BAG RESISTANCE (PS_AB) PID WHILE CARRYING OUT A HARNESS TEST


- Continue monitoring the PS_AB PID while carrying out a harness test of the passenger side air bag circuits and accessible connectors (including any inline connectors), by wiggling connectors and flexing the wire harness.
- Does the resistance PID value read between 1.31 and 4.29 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 H28.

No
If the PS_AB PID is less than 1.31 ohms, GO to H14.

If the PS_AB PID is greater than 4.29 ohms, GO to H17.

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H14 CHECK PASSENGER SIDE AIR BAG MODULE FAULT PIDs FOR A 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 Side Air Bag Module C314.
- 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 (Side Air Bag Circuit Resistance Low, Front Passenger Side)
- 2295_25_OD (Side Air Bag Circuit Open, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2295 on-demand fault PIDs with the passenger side air bag module disconnected, an open circuit fault would normally be retrieved.
- Did the on-demand fault PID change from a low resistance to an open circuit fault?

Yes
GO to H22.

No
GO to H15.

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