B1879 – OBD-II DTC

OBD-II DTC B1879 – Seatbelt Driver Pretensioner Circuit Short to Ground

DTC B1879 meaning

DTC B1879 refers to a diagnostic trouble code indicating a problem with the driver seatbelt pretensioner circuit. Specifically, it signifies a short to ground condition in the circuit that controls the seatbelt pretensioner. The pretensioner is a safety device that tightens the seatbelt during a collision to help secure the occupant in place, reducing the risk of injury.

DTC B1879 symptoms

Common symptoms associated with DTC B1879 may include:

• Illuminated airbag warning light on the dashboard
• Inoperative seatbelt pretensioner
• Possible malfunction of the airbag system
• Increased risk of injury in the event of a collision

DTC B1879 causes

Several factors can lead to the occurrence of DTC B1879, including:

• Damaged wiring or connectors in the seatbelt pretensioner circuit
• Faulty seatbelt pretensioner module
• Corrosion or poor connections in the circuit
• Accidental deployment of the pretensioner
• Issues with the vehicle’s body control module (BCM)

DTC B1879 seriousness

DTC B1879 is considered serious because it directly affects the functionality of the seatbelt pretensioner and, consequently, the overall safety of the vehicle occupants. If the pretensioner is not functioning correctly, it may not deploy in the event of a crash, increasing the risk of injury. It is crucial to address this issue promptly.

How to diagnose DTC B1879

To diagnose DTC B1879, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1879.
2. Inspect the wiring and connectors related to the seatbelt pretensioner for any visible damage or corrosion.
3. Check for any additional DTCs that may provide more context to the issue.
4. Test the seatbelt pretensioner circuit for continuity and resistance using a multimeter.
5. Verify the operation of the seatbelt pretensioner module.

How to fix DTC B1879 step-by-step instructions

To fix DTC B1879, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety while working on the electrical system.
2. Inspect and repair any damaged wiring or connectors in the seatbelt pretensioner circuit.
3. If the pretensioner module is faulty, replace it with a new or refurbished unit.
4. Reconnect all connectors and ensure they are secure.
5. Reconnect the vehicle’s battery.
6. Clear the DTC using an OBD-II scanner and perform a test drive to ensure the issue is resolved.

How to erase DTC B1879

To erase DTC B1879, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the DTC menu on the scanner and select the option to clear or erase codes.
4. Confirm the action and wait for the scanner to complete the process.
5. Disconnect the scanner and start the vehicle to ensure the DTC does not reappear.

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