WOMS
B code body Medium severity

B1674 Seat Driver Occupied Input Circuit Short To Battery

The OBD2 code B1674 indicates a fault in the driver seat occupancy sensor circuit, specifically that there is a short circuit to the battery, which may prevent the system from correctly detecting whether the driver seat...

Definition

The OBD2 code B1674 indicates a fault in the driver seat occupancy sensor circuit, specifically that there is a short circuit to the battery, which may prevent the system from correctly detecting whether the driver seat is occupied

Common causes

  • Shorted wiring or connectors in the seat occupancy sensor circuit
  • Faulty seat occupancy sensor
  • Damaged or corroded connectors
  • Malfunctioning airbag control module
  • Improper installation or modifications to the seat or wiring
  • Grounding issues in the circuit

Common misdiagnoses

  • Faulty seat occupancy sensor
  • Wiring issues or shorts in the harness
  • Malfunctioning airbag control module
  • Defective seat control module
  • Incorrectly installed or damaged seat
  • Issues with the vehicle's body control module (BCM)
  • Faulty connectors or terminals in the circuit

Troubleshooting steps

  1. 1. Verify the Code

    Use an OBD-II scanner to confirm the presence of the B1674 code

  2. 2. Check for any additional codes that may provide more context or related issues

  3. 3. Inspect the Wiring and Connectors

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

  4. 4. Connector Check

    Ensure that all connectors are securely attached and free of dirt or moisture

  5. 5. Test the Seat Occupancy Sensor

    Resistance Check: If accessible, measure the resistance of the seat occupancy sensor. Compare the readings to the manufacturer’s specifications

  6. 6. Functionality Test

    If possible, test the sensor by applying weight to see if the system responds correctly

  7. 7. Check for Short Circuits

    Continuity Test: Use a multimeter to check for continuity in the wiring. Look for any shorts to ground or battery voltage

  8. 8. Voltage Check

    With the ignition on, check for voltage at the sensor connector. Ensure it matches the expected voltage as per the vehicle’s service manual

  9. 9. Inspect the Airbag System

    Since the seat occupancy sensor is often linked to the airbag system, ensure that there are no issues with the airbag module or related components

  10. 10. Check for any other airbag-related codes that may indicate a broader issue

  11. 11. Check for Ground Issues

    Ensure that the ground connections for the seat occupancy sensor and related components are secure and free of corrosion

  12. 12. Look for Related Technical Service Bulletins (TSBs)

    Research if there are any TSBs related to the B1674 code for your specific vehicle make and model. Manufacturers may have known fixes or updates

  13. 13. Clear the Code and Test Drive

    After performing the checks and repairs, clear the code using the OBD-II scanner

  14. 14. Take the vehicle for a test drive to see if the code returns

  15. 15. Consult a Professional

    If the issue persists after following the above steps, it may be necessary to consult a professional mechanic or technician who has experience with your vehicle’s specific systems

  16. 16. Replace Components if Necessary

    If the sensor or wiring is found to be faulty, replace the necessary components as per the manufacturer’s specifications. By following these steps, you should be able to identify and resolve the issue related to the B1674 code. Always refer to the vehicle’s service manual for specific details and specifications related to your make and model