WOMS
B code body Medium severity

B1673 Seat Driver Occupied Input Circuit Open

The OBD2 code B1673 indicates that there is an open circuit in the driver seat occupancy sensor input, meaning the system is not detecting whether the driver seat is occupied

Definition

The OBD2 code B1673 indicates that there is an open circuit in the driver seat occupancy sensor input, meaning the system is not detecting whether the driver seat is occupied

Common causes

  • Faulty seat occupancy sensor
  • Damaged wiring or connectors in the seat occupancy circuit
  • Poor ground connection
  • Malfunctioning airbag control module
  • Corroded or loose connections
  • Faulty seat control module
  • Disconnected or damaged harnesses

Common misdiagnoses

  • Faulty seat occupancy sensor
  • Wiring issues or shorts in the seat harness
  • Malfunctioning airbag control module
  • Faulty seat control module
  • Issues with the vehicle's body control module (BCM)
  • Problems with the connector or terminals related to the seat sensor
  • Incorrectly installed or damaged seat assembly

Troubleshooting steps

  1. 1. Check the Basics

    Scan for Codes: Use an OBD-II scanner to confirm the presence of the B1673 code and check for any other related codes that might provide additional context

  2. 2. Clear Codes

    Clear the codes and see if the B1673 code returns after a short drive. This can help determine if it’s a persistent issue

  3. 3. Inspect the Wiring and Connectors

    Visual Inspection: Check the wiring and connectors associated with the driver’s seat occupancy sensor. Look for any signs of damage, corrosion, or loose connections

  4. 4. Connector Pins

    Ensure that the pins in the connectors are not bent, corroded, or pushed out

  5. 5. Test the Seat Occupancy Sensor

    Sensor Functionality: If the vehicle is equipped with a seat occupancy sensor, test its functionality. This may involve checking the resistance or voltage output of the sensor when the seat is occupied versus unoccupied

  6. 6. Sensor Replacement

    If the sensor is faulty, consider replacing it

  7. 7. Check for Ground Issues

    Ground Connections: Ensure that the ground connections for the seat occupancy sensor circuit are secure and free of corrosion. A poor ground can lead to an open circuit

  8. 8. Inspect the Airbag Module

    Airbag Module Connection: Since the seat occupancy sensor is often tied to the airbag system, check the connections to the airbag module for any issues

  9. 9. Module Functionality

    If necessary, test the airbag module to ensure it is functioning correctly

  10. 10. Look for Shorts or Opens in the Circuit

    Continuity Testing: Use a multimeter to check for continuity in the wiring between the seat occupancy sensor and the airbag module. Look for any breaks or shorts in the wiring

  11. 11. Resistance Testing

    Measure the resistance of the circuit to ensure it is within the manufacturer’s specifications

  12. 12. Consult Wiring Diagrams

    Wiring Diagrams: Refer to the vehicle’s service manual for wiring diagrams to understand the circuit layout and identify any other components that may be involved

  13. 13. Check for Software Updates

    ECU Updates: In some cases, a software update for the vehicle’s ECU may resolve the issue. Check with the manufacturer or a dealership for any available updates

  14. 14. Professional Diagnosis

    If the issue persists after performing the above steps, consider seeking help from a professional mechanic or dealership. They may have specialized diagnostic tools and experience with the specific vehicle model.Conclusion By following these troubleshooting steps, you should be able to identify the cause of the B1673 code and take appropriate action to resolve it. Always refer to the vehicle’s service manual for specific procedures and specifications related to your vehicle model