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Pinpoint Test D: DTC B1884




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

Pinpoint Tests

Pinpoint Test D: DTC B1884

Refer to Wiring Diagram Set 46, Supplemental Restraint System for schematic and connector information. Diagrams By Number

Normal Operation

When the ignition is in the ON position, the Passenger Air Bag Deactivation (PAD) indicator prove-out period is initiated by the Restraints Control Module (RCM). The RCM briefly activates the PAD indicator to verify to the occupants correct functional operation of the PAD indicator. Refer to Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS) Description and Operation.

If the RCM detects an open or short to ground on the PAD indicator circuit, it will store DTC B1884 in memory and send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

- DTC B1884 PAD Warning Lamp Circuit Failure - If the RCM detects an open circuit or short to ground on the PAD indicator circuit, it will set this DTC.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Passenger Air Bag Deactivation (PAD) indicator
- RCM



PINPOINT TEST D: DTC B1884

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: Always tighten the fasteners of the restraints control module (RCM) and impact sensor (if equipped) to the specified torque. Failure to do so may result in incorrect restraint system operation, which increases the risk of personal injury or death in a crash.

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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D1 RETRIEVE RCM DTCs


- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Was DTC B1884 retrieved on-demand during self-test?

Yes
If the PAD indicator does illuminate, GO to D2.
If the PAD indicator does not illuminate, GO to D4.

No
This is an intermittent fault when present as a CMDTC only. The fault condition is not present at this time. GO to D8.

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D2 CHECK CIRCUIT CR116 (GN/WH) FOR 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: PAD Indicator C2286.
- Measure resistance between PAD indicator C2286-3, circuit CR116 (GN/WH), harness side and ground.




- Is resistance greater than 10,000 ohms?

Yes
GO to D7.

No
GO to D3.

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D3 CHECK THE RCM FOR LOW RESISTANCE


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




- Is resistance greater than 10,000 ohms?

Yes
REPAIR circuit CR116 (GN/WH). GO to D9.

No
GO to D7.

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D4 CHECK PAD INDICATOR CIRCUIT FOR AN OPEN


- 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.
- Disconnect: PAD Indicator C2286.
- Measure resistance between PAD indicator C2286-3, circuit CR116 (GN/WH), harness side and RCM C310a-22, circuit CR116 (GN/WH), harness side.




- Is resistance less than 0.5 ohm?

Yes
GO to D5.

No
REPAIR circuit CR116 (GN/WH). GO to D9.

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D5 CHECK PAD IGNITION CIRCUIT FOR VOLTAGE


- 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 PAD indicator C2286-1, circuit CBP17 (BN/GN), harness side and ground.




- Is voltage greater than 10 volts?

Yes
GO to D6.

No
REPAIR circuit CBP17 (BN/GN). GO to D9.

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D6 CHECK THE PAD INDICATOR


- Ignition OFF.
- Deactivate the SRS. Refer to Supplemental Restraint System (SRS) Deactivation and Reactivation Supplemental Restraint System (SRS) Deactivation and Reactivation.
- Connect: PAD Indicator C2286.
- Ignition ON.
- Connect a fused jumper wire between RCM C310a-22, circuit CR116 (GN/WH), harness side and ground.




- Does the PAD indicator illuminate?

Yes
GO to D7.

No
INSTALL a new PAD indicator. REFER to Passenger Air Bag Deactivation (PAD) Indicator Service and Repair.
GO to D9.

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D7 CONFIRM THE RCM FAULT


NOTE: Make sure all restraint system components, sensor electrical connectors and the RCM electrical connectors are connected before carrying out the on-demand self test. If not, 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: PAD Indicator C2286 (if disconnected in prior step).
- Connect: RCM C310a and C310b (if disconnected in prior step).
- 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.
- Was on-demand DTC B1884 retrieved on-demand during self-test?

Yes
INSTALL a new RCM. REFER to Restraints Control Module (RCM) Service and Repair. GO to D9.

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 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 D9.

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D8 CHECK FOR AN INTERMITTENT FAULT


- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Was DTC B1884 retrieved on-demand during self-test?

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. GO to D2.

No
The fault is not present and cannot be recreated at this time.

CHECK for causes of intermittent open or short to ground on circuit CR116 (GN/WH). ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition 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, terminal or connector concerns found. GO to D9.

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D9 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.
- If previously directed to deactivate the SRS, reactivate the SRS. Do notprove out the SRS at this time. Refer to Supplemental Restraint System (SRS) Deactivation and Reactivation Supplemental Restraint System (SRS) Deactivation and Reactivation.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - Restraints.
- Are any RCM and/or OCSM DTCs indicating a fault?

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 and OCSM CMDTCs. PROVE OUT the SRS. REPAIR is complete. RETURN the vehicle to the customer.

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