B1901 – OBD-II DTC

OBD-II DTC B1901 – Air Bag Crash Sensor #1 Feed/Return Circuit Short To Ground

DTC B1901 meaning

DTC B1901 refers to a diagnostic trouble code indicating a problem with the airbag system, specifically related to the crash sensor #1 feed/return circuit. This code suggests that there is a short circuit to ground in the wiring or components associated with the crash sensor, which is crucial for the proper deployment of airbags during a collision.

DTC B1901 symptoms

Common symptoms associated with DTC B1901 may include:

• Illumination of the airbag warning light on the dashboard
• Potential malfunction of the airbag system
• Inconsistent airbag deployment during a crash
• Diagnostic trouble codes related to the airbag system

DTC B1901 causes

Several factors can lead to the occurrence of DTC B1901, including:

• Damaged wiring or connectors in the crash sensor circuit
• Corrosion or poor connections at the sensor or module
• Faulty crash sensor #1
• Issues with the airbag control module
• Accidental grounding of the circuit

DTC B1901 seriousness

DTC B1901 is considered serious because it directly affects the airbag system’s functionality. If the airbag system is compromised, it may not deploy in the event of a collision, increasing the risk of injury to the occupants. Therefore, it is crucial to address this code promptly to ensure passenger safety.

How to diagnose DTC B1901

To diagnose DTC B1901, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC B1901.
2. Inspect the wiring and connectors associated with crash sensor #1 for damage or corrosion.
3. Check for any additional DTCs that may provide more context to the issue.
4. Test the resistance and continuity of the sensor circuit.
5. Verify the functionality of crash sensor #1 using a multimeter.
6. Examine the airbag control module for faults or issues.

How to fix DTC B1901 step-by-step instructions

To fix DTC B1901, follow these steps:

1. Disconnect the vehicle’s battery to ensure safety while working on the airbag system.
2. Inspect and repair any damaged wiring or connectors in the crash sensor circuit.
3. Replace crash sensor #1 if it is found to be faulty.
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 verify that the code does not return.

How to erase DTC B1901

To erase DTC B1901, 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 option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase DTC B1901.
5. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

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