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Home >> Lincoln >> 2009 >> MKZ AWD V6-3.5L >> Repair and Diagnosis >> Restraints and Safety Systems >> Air Bag Systems >> Testing and Inspection >> Pinpoint Tests >> Pinpoint Tests - Restraints Control Module (RCM) >> Pinpoint Test F: DTC B2293 >> F29-F43

F29-F43




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

Pinpoint Tests - Restraints Control Module (RCM)

Pinpoint Test F: DTC B2293

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 all front air bag module circuits (loop) for an acceptable resistance range, unacceptable voltage and shorts to ground. The RCM will store DTC B2293 in memory if any of these conditions are detected. If the RCM detects a fault on any of the front air bag circuits, it will store DTC B2293 in memory and send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

As the RCM continuously monitors all front air bag module circuits for resistance, it expects a normal resistance for the driver and passenger air bag modules loop 1 and 2, between 1.31 to 4.29 ohms.

If a loop resistance for the driver and/or passenger air bag loop 1 and/or 2 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 B2293. Fault PIDs that end in CM indicate continuous memory status and are associated with continuous DTC B2293.

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



PINPOINT TEST F: DTC B2293

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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F29 CHECK PASSENGER AIR BAG MODULE LOOP 1 RESISTANCE (P_ABAGR) PID WHILE CARRYING OUT A HARNESS TEST


- With the passenger air bag in its mounted position, continue monitoring the P_ABAGR PID while carrying out a harness test of the passenger air bag module 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 F56.

No
If the P_ABAGR PID is less than 1.31 ohms, GO to F30.

If the P_ABAGR PID is greater than 4.29 ohms, GO to F32.

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F30 CHECK PASSENGER AIR BAG MODULE LOOP 1 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 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.
- 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.
- 2293_24_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side)
- 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the on-demand fault PID change from a low resistance to an open circuit fault?

Yes
GO to F47.

No
GO to F31.

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F31 CHECK RCM FOR LOW RESISTANCE


- 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 RCM C310a pin 1 and pin 2, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR103 (GY/BU) and RR103 (VT/GN). GO to F56.

No
GO to F49.

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F32 CHECK PASSENGER AIR BAG MODULE LOOP 1 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: Passenger Air Bag Module C256a and C256b.
- Connect a jumper wire between passenger air bag module C256a-1, circuit CR103 (GY/BU), harness side and C256a-2, circuit RR103 (VT/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.
- 2293_24_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side)
- 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module loop 1 circuits shorted together, a low resistance fault would normally be retrieved on loop 1. Loop 2 will show an open circuit fault due to the passenger air bag being disconnected.
- Did the on-demand fault PID change from an open circuit to a low resistance fault?

Yes
GO to F47.

No
GO to F33.

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F33 CHECK PASSENGER AIR BAG MODULE LOOP 1 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 passenger air bag module C256.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310a-1, circuit CR103 (GY/BU), harness side and passenger air bag module C256a-1, circuit CR103 (GY/BU), harness side.




- Measure resistance between RCM C310a-2, circuit RR103 (VT/GN), harness side and passenger air bag module C256a-2, circuit RR103 (VT/GN), harness side.




- Are the resistances less than 0.5 ohm?

Yes
GO to F49.

No
REPAIR circuit CR103 (GY/BU) or RR103 (VT/GN). GO to F56.

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F34 CHECK PASSENGER AIR BAG MODULE LOOP 1 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: Passenger Air Bag Module C256a.
- 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.
- 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side)
- 2293_27_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the on-demand fault PID change from a short to ground to an open circuit fault?

Yes
GO to F47.

No
GO to F35.

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F35 CHECK PASSENGER AIR BAG MODULE LOOP 1 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 passenger air bag module:
- C256a-1, circuit CR103 (GY/BU), harness side and ground.
- C256a-2, circuit RR103 (VT/GN), harness side and ground.




- Are the resistances greater than 10,000 ohms?

Yes
GO to F49.

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 CR103 (GY/BU) or RR103 (VT/GN). GO to F56.

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F36 CHECK PASSENGER AIR BAG MODULE LOOP 1 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 Air Bag Module C256.
- 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:
- passenger air bag module C256a-1, circuit CR103 (GY/BU), harness side and ground.
- passenger air bag module C256a-2, circuit RR103 (VT/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 CR103 (GY/BU) or RR103 (VT/GN). GO to F56.

No
GO to F49.

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F37 CHECK PASSENGER AIR BAG MODULE LOOP 2 RESISTANCE (P_ABAGR2) PID


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - PID.
- Enter the following diagnostic mode on the scan tool: P_ABAGR2 PID.
- Does the resistance PID value read between 1.31 and 4.29 ohms?

Yes
GO to F49.

No
GO to F38.

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F38 CHECK PASSENGER AIR BAG MODULE LOOP 2 RESISTANCE (P_ABAGR2) PID WHILE CARRYING OUT A HARNESS TEST


- NOTE: Do not remove the passenger air bag module from its mounted position at this time.
- With the passenger air bag in its mounted position, continue monitoring the P_ABAGR2 PID while carrying out a harness test of the passenger air bag module 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 F56.

No
If the P_ABAGR2 PID is less than 1.31 ohms, GO to F39.

If the P_ABAGR2 PID is greater than 4.29 ohms, GO to F41.

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F39 CHECK PASSENGER AIR BAG MODULE LOOP 2 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 Air Bag Module C256a and C256b.
- 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.
- 2293_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side)
- 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the on-demand fault PID change from a low resistance to an open circuit fault?

Yes
GO to F47.

No
GO to F40.

-------------------------------------------------
F40 CHECK RCM FOR LOW RESISTANCE


- 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 RCM C310a pin 5 and C310a pin 6, component side.




- Is the resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR104 (YE/GY) and RR104 (WH/BU). GO to F56.

No
GO to F49.

-------------------------------------------------
F41 CHECK PASSENGER AIR BAG MODULE LOOP 2 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: Passenger Air Bag Module C256a and C256b.
- Connect a jumper wire between passenger air bag module C256b-1, circuit CR104 (YE/GY), harness side and C256b-2, circuit RR104 (WH/BU), 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.
- 2293_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side)
- 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module loop 2 circuits shorted together, a low resistance fault would normally be retrieved on loop 2. Loop 1 will show an open circuit fault due to the passenger air bag module being disconnected.
- Did the on-demand fault PID change from an open circuit to a low resistance fault?

Yes
GO to F47.

No
GO to F42.

-------------------------------------------------
F42 CHECK PASSENGER AIR BAG MODULE LOOP 2 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 passenger air bag module C256.
- Disconnect: RCM C310a and C310b.
- Measure resistance between RCM C310a-5, circuit CR104 (YE/GY), harness side and passenger air bag module C256b-1, circuit CR104 (YE/GY), harness side.




- Measure resistance between RCM C310a-6, circuit RR104 (WH/BU), harness side and passenger air bag module C256b-2, circuit RR104 (WH/BU), harness side.




- Are the resistances less than 0.5 ohm?

Yes
GO to F49.

No
REPAIR circuit CR104 (YE/GY) or RR104 (WH/BU). GO to F56.

-------------------------------------------------
F43 CHECK PASSENGER AIR BAG MODULE LOOP 2 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: Passenger Air Bag Module C256a and C256b.
- 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.
- 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side)
- 2293_19_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the passenger air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the on-demand fault PID change from a short to ground to an open circuit fault?

Yes
GO to F47.

No
GO to F44.

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