Pinpoint Test G: LFC 18/DTC B1884
Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)
Pinpoint Tests
Pinpoint Test G: LFC 18 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, the RCM briefly activates the PAD indicator to verify to the occupants correct functional 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 to flash Lamp Fault Code (LFC) 18 on the air bag warning indicator. After the LFC(s) are displayed, the air bag warning indicator will remain illuminated for the rest of the ignition cycle.
- DTC B1884 PAD Warning Lamp Circuit Failure - If the RCM detects an open or short to ground when the indicator is not active for greater than 2.2 seconds on the PAD indicator circuit, it will set this DTC.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- PAD indicator
- RCM
PINPOINT TEST G: LFC 18 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.
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: SRScomponents 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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G1 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 is illuminated continuously, GO to G2.
If the PAD indicator does not illuminate, GO to G4.
No
This is an intermittent fault when present as a CMDTC only. The fault condition is not present at this time. GO to G8.
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G2 CHECK THE PAD INDICATOR CIRCUIT 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: Front Controls Interface Module (FCIM) C2403 or HVAC - DATC C228c.
- Measure resistance between:
- FCIM C2403-10, circuit RR116 (BN/GN), harness side and ground.
- HVAC - DATC C228c-10, circuit RR116 (BN/GN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to G6.
No
GO to G3.
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G3 CHECK THE RCM FOR LOW RESISTANCE
- Disconnect: RCM C310a and C310b.
- Measure the resistance between RCM C310a pin 22, component side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
REPAIR circuit RR116 (BN/GN). GO to G8.
No
GO to G6.
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G4 CHECK THE 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: FCIM C2403 or HVAC - DATC C228c.
- Measure resistance between:
- RCM C310a-22, circuit RR116 (BN/GN), harness side and front control interface module C2403-10, circuit RR116 (BN/GN), harness side.
- RCM C310a-22, circuit RR116 (BN/GN), harness side and HVAC - DATC C228c-10, circuit RR116 (BN/GN), harness side.
- Is the resistance less than 0.5 ohm?
Yes
GO to G5.
No
REPAIR circuit RR116 (BN/GN). GO to G8.
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G5 CHECK THE PAD INDICATOR
- Connect: FCIM C2403 or HVAC - DATC C228c.
- Connect a fused jumper wire between RCM C310a-22, circuit RR116 (BN/GN), harness side and ground.
- Vehicles with Push-Button Start System:
- Remove Battery Junction Box (BJB) relay 56.
- Install a 20A fused jumper wire in BJB at relay 56 cavities as shown.
- Vehicles with ignition switch:
- Turn the ignition ON.
- WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
- Connect the battery ground cable.
- Monitor the PAD indicator.
- Does the PAD indicator illuminate?
Yes
GO to G6.
No
INSTALL a new PAD indicator. REFER to Passenger Air Bag Deactivation (PAD) Indicator Service and Repair.
GO to G8.
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G6 CONFIRM THE RCM FAULT
NOTE: Make sure all restraint system diagnostic tools, sensor electrical connectors and the RCM electrical connector are connected before carrying out the on-demand self test. If not, erroneous DTCs will be recorded.
- Ignition OFF.
- Disconnect the battery ground cable.
- Remove the fused jumper wires. (If previously installed).
- Connect: FCIM C2403 or HVAC - DATC C228c (if previously disconnected).
- Connect: RCM C310a and C310b (if previously disconnected).
- 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 DTC B1884 retrieved on-demand during self-test?
Yes
INSTALL a new RCM and CARRY OUT Programmable Module Installation (PMI) Programming and Relearning. REFER to Restraints Control Module (RCM) Service and Repair. GO to G8.
No
In the process of diagnosing the fault, the fault condition has become intermittent. 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. GO to G7.
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G7 CHECK FOR AN INTERMITTENT FAULT
- Ignition OFF.
- Depower the SRS. Refer to Supplemental Restraint System (SRS) Depowering and Repowering Supplemental Restraint System (SRS) Depowering and Repowering.
- Inspect for the following:
- inspect harness and component connectors for loose or spread terminals and loose or frayed wire connections at terminals.
- inspect wire harness for any damage, pinched, cut or pierced wires.
- repair any concerns found. Refer to Wiring Diagram Set 5, Connector Repair Procedures for schematic and connector information. Diagrams By Number
- Enter the following diagnostic mode on the scan tool: Self Test - RCM.
- Was DTC B1884 retrieved on-demand during self-test?
Yes
This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self test. GO to G2.
No
CHECK for causes of intermittent open or short to ground on circuit RR116 (BN/GN). ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key 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 G8.
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G8 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.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self Test - Restraints.
- NOTE: When selecting Restraints from the Self Test menu, DTCs will be retrieved from the RCM and OCSM.
- Are any RCM and/or OCSM DTCs retrieved on-demand during self-test?
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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