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H1-H10




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

Pinpoint Tests

Pinpoint Test H: LFC 19/21 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 set on-demand and store DTC B2293 in memory if any of these conditions are detected to be outside of their respectful range. If the RCM detects a fault, it will send a message to the Instrument Cluster (IC) module to flash a Lamp Fault Code (LFC) 19 or 21 on 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 air bag module loop 1 and 2, between 1.84 and 3.96 ohms. The normal expected resistance for the passenger air bag module loop 1 and 2 is between 1.50 and 3.04 ohms.

If a loop resistance for the driver air bag loop 1 or 2 is between 1.36 and 1.84 ohms or between 3.96 and 4.70 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 1.36 ohms or greater than 4.70 ohms.

If loop resistance for passenger air bag loop 1 or 2 is between 1.04 and 1.50 ohms or between 3.04 and 3.72 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 1.04 ohms or greater than 3.72 ohms.

NOTE: When monitoring fault and/or resistance PIDs with the scan tool, it may take up to 2 seconds for the scan tool display to update.





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
- Passenger air bag module
- RCM



PINPOINT TEST H: LFC 19/21 DTC B2293

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 taking 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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H1 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 B2293 Fault PIDs.
- Refer to PID list in Normal Operation to view B2293 fault PIDs.
- Do any RCM on-demand B2293 fault PIDs indicate a fault?

Yes
This is a hard fault. 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 on-demand fault PIDs recorded, GO to the appropriate pinpoint test step.

For 2293_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side), GO to H2.

For 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side), GO to H2.

For 2293_31_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side), GO to H10.

For 2293_30_OD (Air Bag Circuit Short to Battery - Loop No. 1, Front Driver Side), GO to H13.

For 2293_20_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Driver Side), GO to H15.

For 2293_21_OD (Air Bag Circuit Open - Loop No. 2, Front Driver Side), GO to H15.

For 2293_23_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Driver Side), GO to H23.

For 2293_22_OD (Air Bag Circuit Short to Battery - Loop No. 2, Front Driver Side), GO to H26.

For 2293_24_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side), GO to H28.

For 2293_25_OD (Air Bag Circuit Open - Loop No. 1, Front Passenger Side), GO to H28.

For 2293_27_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side), GO to H34.

For 2293_26_OD (Air Bag Circuit Short to Battery - Loop No. 1, Front Passenger Side), GO to H36.

For 2293_16_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side), GO to H37.

For 2293_17_OD (Air Bag Circuit Open - Loop No. 2, Front Passenger Side), GO to H37.

For 2293_19_OD (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side), GO to H43.

For 2293_18_OD (Air Bag Circuit Short to Battery - Loop No. 2, Front Passenger Side), GO to H45.

No
This is an intermittent fault when present as a continuous memory DTC only (DTC not retrieved on-demand). The fault condition is not present at this time.

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

For 2293_28_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side) or 2293_20_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Driver Side), GO to H50.

For 2293_29_CM (Air Bag Circuit Open - Loop No. 1, Front Driver Side) or 2293_21_CM (Air Bag Circuit Open - Loop No. 2, Front Driver Side), GO to H50.

For 2293_31_CM (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side) or 2293_23_CM (Air Bag Circuit Short to Ground - Loop No. 2, Front Driver Side), GO to H51.

For 2293_30_CM (Air Bag Circuit Short to Battery - Loop No. 1, Front Driver Side) or 2293_22_CM (Air Bag Circuit Short to Battery - Loop No. 2, Front Driver Side), GO to H53.

For 2293_24_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Passenger Side) or 2293_16_CM (Air Bag Inflator Circuit Resistance Low - Loop No. 2, Front Passenger Side), GO to H50.

For 2293_25_CM (Air Bag Circuit Open - Loop No. 1, Front Passenger Side) or 2293_17_CM (Air Bag Circuit Open - Loop No. 2, Front Passenger Side), GO to H50.

For 2293_27_CM (Air Bag Circuit Short to Ground - Loop No. 1, Front Passenger Side) or 2293_19_CM (Air Bag Circuit Short to Ground - Loop No. 2, Front Passenger Side), GO to H52.

For 2293_26_CM (Air Bag Circuit Short to Battery - Loop No. 1, Front Passenger Side) or 2293_18_CM (Air Bag Circuit Short to Battery - Loop No. 2, Front Passenger Side), GO to H54.

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H2 CHECK THE DRIVER AIR BAG MODULE LOOP 1 RESISTANCE PID (D_ABAGR)


- Enter the following diagnostic mode on the scan tool: DataLogger - RCM - PID.
- Enter the following diagnostic mode on the scan tool: D_ABAGR (Driver Air Bag) Resistance PID.
- Does resistance PID value read PID between 1.84 and 3.96 ohms?

Yes
GO to H49.

No
GO to H3.

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H3 CHECK THE DRIVER AIR BAG MODULE LOOP 1 RESISTANCE PID (D_ABAGR) WHILE CARRYING OUT A HARNESS TEST


- NOTE: Do not remove the driver air bag module from its mounted position at this time.
- With the driver air bag in its mounted position, continue monitoring the D_ABAGR (Driver Air Bag) resistance PID while carrying out a harness test of the driver air bag circuits and accessible connectors (including any in-line connectors) by wiggling and flexing the wire harness, connectors, tilting and rotating the steering wheel frequently.
- Does resistance PID value read between 1.84 and 3.96 ohms while carrying out the harness test?

Yes
DEPOWER the SRS and REPAIR the connector, terminals or wire harness or INSTALL a new clockspring as needed. REFER to Clockspring Service and Repair.
Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
GO to H56.

No
If the driver air bag module loop 1 resistance PID is less than 1.84 ohms, GO to H4.

If the driver air bag module loop 1 resistance PID is greater than 3.96 ohms, GO to H7.

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H4 CHECK THE DRIVER AIR BAG MODULE LOOP 1 CIRCUIT FAULT PIDs (2293_28_OD AND 2293_29_OD) FOR LOW RESISTANCE AND OPEN


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.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- 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_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PIDs change from indicating a low resistance to an open circuit fault?

Yes
GO to H46.

No
GO to H5.

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H5 CHECK THE DRIVER AIR BAG MODULE LOOP 1 CIRCUIT FAULT PIDs (2293_28_OD AND 2293_29_OD) FOR LOW RESISTANCE AND OPEN (CLOCKSPRING DISCONNECTED)


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.
- Disconnect: Clockspring C218a.
- 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_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module/clockspring disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PIDs change from indicating a low resistance to an open circuit fault?

Yes
GO to H48.

No
GO to H6.

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H6 CHECK THE 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 the resistance between RCM C310a pin 3 and C310a pin 4, component side.




- Is resistance greater than 10,000 ohms?

Yes
REPAIR circuits CR101 (VT/BN) and RR101 (YE/GN). GO to H56.

No
GO to H49.

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H7 CHECK THE DRIVER AIR BAG MODULE LOOP 1 CIRCUIT FAULT PIDs (2293_29_OD AND 2293_28_OD) FOR AN OPEN AND LOW RESISTANCE


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.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- Connect a fused jumper wire between driver air bag module loop 1 electrical connector pin-1, harness side and pin-2, 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_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver 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 driver air bag being disconnected.
- Did the driver air bag module loop 1 on-demand fault PIDs change from indicating an open circuit to a low resistance fault?

Yes
GO to H46.

No
GO to H8.

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H8 CHECK THE DRIVER AIR BAG MODULE LOOP 1 CIRCUIT FAULT PIDs (2293_29_OD AND 2293_28_OD) FOR LOW RESISTANCE AND OPEN (CLOCKSPRING DISCONNECTED)


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.
- Remove the fused jumper wire from driver air bag module loop 1 electrical connector.
- Disconnect: Clockspring C218a.
- Connect a fused jumper wire between clockspring C218a-1, circuit CR101 (VT/BN), harness side and clockspring C218a-9, circuit RR101 (YE/GN), harness side.
- 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_28_OD (Air Bag Inflator Circuit Resistance Low - Loop No. 1, Front Driver Side)
- 2293_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver 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 driver air bag being disconnected.
- Did the driver air bag module loop 1 on-demand fault PIDs change from indicating an open circuit to a low resistance fault?

Yes
GO to H48.

No
GO to H9.

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H9 CHECK DRIVER AIR BAG MODULE LOOP 1 CIRCUITS CR101 (VT/BN) AND RR101 (YE/GN) FOR AN OPEN BETWEEN THE CLOCKSPRING AND RCM


- 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 clockspring connector.
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310a, harness side and clockspring C218a, harness side using the following chart.









- Are resistances less than 0.5 ohm?

Yes
GO to H49.

No
REPAIR circuit CR101 (VT/BN) or RR101 (YE/GN). GO to H56.

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H10 CHECK THE DRIVER AIR BAG MODULE LOOP 1 CIRCUIT FAULT PIDs (2293_31_OD AND 2293_29_OD) FOR A SHORT TO GROUND AND OPEN


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.
- Remove the driver air bag module. Refer to Driver Air Bag Module Driver Air Bag Module.
- 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_29_OD (Air Bag Circuit Open - Loop No. 1, Front Driver Side)
- 2293_31_OD (Air Bag Circuit Short to Ground - Loop No. 1, Front Driver Side)
- DIAGNOSTIC TIP: When viewing DTC B2293 on-demand fault PIDs with the driver air bag module disconnected, open circuit faults would normally be retrieved on loop 1 and loop 2.
- Did the driver air bag module loop 1 on-demand fault PIDs change from indicating a short to ground to an open circuit fault?

Yes
GO to H46.

No
GO to H11.

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