B1905: Air Bag Crash Sensor #2 Feed/Return Circuit Short To Battery

Definition

The OBD2 code B1905 indicates a short circuit in the feed or return circuit of Air Bag Crash Sensor #2, which means there is an electrical fault causing the sensor to receive constant battery voltage instead of the expected signal

Common causes

Damaged wiring or connectors
Short circuit in the feed/return circuit
Faulty airbag crash sensor
Corrosion in electrical connections
Improper installation or modifications
Faulty airbag control module
Grounding issues in the circuit

Common misdiagnoses

Faulty airbag control module
Defective crash sensor
Wiring issues or shorts in the harness
Poor ground connections
Faulty seat belt pretensioner
Malfunctioning airbag indicator light
Issues with the vehicle's body control module (BCM)
Battery or charging system problems

Troubleshooting steps

1. Scan Tool Verification
2. Use an OBD-II scanner to confirm the presence of the B1905 code. Check for any additional codes that may provide more context
3. Visual Inspection
4. Inspect the wiring and connectors associated with the airbag system, particularly those related to Crash Sensor #2. Look for signs of damage, corrosion, or loose connections
5. Check the airbag module and sensor mounting points for any signs of impact or physical damage
6. Check for Shorts
7. Use a multimeter to check for continuity in the feed and return circuits of the crash sensor. Look for any shorts to ground or battery voltage
8. Disconnect the sensor and measure the resistance of the circuit. Compare the readings to the manufacturer's specifications
9. Inspect the Crash Sensor
10. If the wiring appears intact, the crash sensor itself may be faulty. Test the sensor according to the manufacturer's specifications or replace it with a known good unit to see if the code clears
11. Check the Airbag Module
12. Inspect the airbag control module for any signs of damage or corrosion. Ensure that all connections are secure
13. If possible, perform a reset of the airbag module using a scan tool to see if the code returns
14. Check for Ground Issues
15. Ensure that the ground connections for the airbag system are secure and free of corrosion. A poor ground can cause various issues, including false codes
16. Inspect Related Components
17. Check other components in the airbag system, such as the seat belt tensioners and other crash sensors, for proper operation
18. Clear the Code
19. After performing repairs or inspections, clear the code using the scan tool and take the vehicle for a test drive to see if the code returns
20. Consult Technical Service Bulletins (TSBs)
21. Look for any TSBs related to the airbag system for your specific vehicle make and model. There may be known issues or recalls that could be relevant
22. Professional Diagnosis
23. If the issue persists after following these steps, consider seeking help from a professional technician who specializes in automotive electrical systems or airbag systems. Always remember to take proper safety precautions when working with airbag systems, as they can deploy unexpectedly and cause injury. If you're unsure about any step, it's best to consult a professional

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Scan Tool Verification

2. Use an OBD-II scanner to confirm the presence of the B1905 code. Check for any additional codes that may provide more context

3. Visual Inspection

4. Inspect the wiring and connectors associated with the airbag system, particularly those related to Crash Sensor #2. Look for signs of damage, corrosion, or loose connections

5. Check the airbag module and sensor mounting points for any signs of impact or physical damage

6. Check for Shorts

7. Use a multimeter to check for continuity in the feed and return circuits of the crash sensor. Look for any shorts to ground or battery voltage

8. Disconnect the sensor and measure the resistance of the circuit. Compare the readings to the manufacturer's specifications

9. Inspect the Crash Sensor

10. If the wiring appears intact, the crash sensor itself may be faulty. Test the sensor according to the manufacturer's specifications or replace it with a known good unit to see if the code clears

11. Check the Airbag Module

12. Inspect the airbag control module for any signs of damage or corrosion. Ensure that all connections are secure

13. If possible, perform a reset of the airbag module using a scan tool to see if the code returns

14. Check for Ground Issues

15. Ensure that the ground connections for the airbag system are secure and free of corrosion. A poor ground can cause various issues, including false codes

16. Inspect Related Components

17. Check other components in the airbag system, such as the seat belt tensioners and other crash sensors, for proper operation

18. Clear the Code

19. After performing repairs or inspections, clear the code using the scan tool and take the vehicle for a test drive to see if the code returns

20. Consult Technical Service Bulletins (TSBs)

21. Look for any TSBs related to the airbag system for your specific vehicle make and model. There may be known issues or recalls that could be relevant

22. Professional Diagnosis