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B1902 is a diagnostic trouble code (DTC) for "Air Bag Crash Sensor #1 Ground Circuit Failure". This can happen for multiple reasons and a mechanic needs to diagnose the specific cause for this code to be triggered in your situation. Our certified mobile mechanics can come to your home or office to perform the Check Engine Light diagnostic for $154.99 . Once we are able to diagnose the problem, you will be provided with an upfront quote for the recommended fix and receive $50.0 off as a credit towards the repair. All our repairs are backed by our 12-month / 12,000-mile warranty.
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The B1902 trouble code notes an electrical malfunction from the airbag crash sensor #1 circuit.
The B1902 code is a generic OBD-II trouble code that detects a problem with the airbag crash sensor #1 circuit. The airbag crash sensor is used to detect when the vehicle is in a collision, so that the airbags can be deployed. Different vehicles have a different number of crash sensors throughout the car, so the location of the #1 sensor varies from model to model. If at any point an abnormal voltage reading from the crash sensor circuit is detected by the airbag control module, body control module, or powertrain control module (PCM), then the B1902 trouble code may be triggered.
The B1902 code is usually caused by one of two things: either damaged electrical components (wires, fuses, connectors, and circuits), or a faulty #1 airbag crash sensor. A defective PCM, body control module, or airbag control module can also cause the B1902 code to be stored, though this is very rare.
When the B1902 trouble code is detected, the check engine soon warning light will likely illuminate on the gauge cluster, and the airbag warning light may do the same. The airbag system will likely not function, meaning that the vehicle will not have airbags should an accident occur.
The B1902 code will be diagnosed with an OBD-II trouble code scanner. A trustworthy technician will view the freeze frame data on the scanner and assess the B1902 code, while also checking to see if any additional trouble codes have been detected. If there are numerous codes present, they will need to be inspected in the order in which the scanner displays them. Next, the trouble codes will be reset, and the vehicle restarted, so the technician can see if the B1902 code remains stored. If it no longer does, then an intermittent error, or an incorrect detection are likely to blame.
If the B1902 code remains, then the technician will begin with a visual inspection of the electrical components in the system. Any wires that are shorted, connectors that are open or corroded, or fuses that are blown will need to be replaced. The circuit will then need to be tested, and then the airbag crash sensor should be inspected.
Any time a component is repaired or replaced, the mechanic will reset the codes, restart the vehicle, and again check for the B1902 code. By doing this, the technician will be alerted as soon as the issue has been resolved.
The most commonly made error when diagnosing this code comes from not complying with the OBD-II trouble code diagnosis protocol. It is imperative that mechanics abide by the protocol at all times, to make sure that diagnoses are efficient and repairs are accurate.
Often, fully functional airbag crash sensors are condemned because electrical errors are overlooked.
A vehicle with a B1902 trouble code will still be completely drivable. However, the airbags will likely fail to deploy if an accident occurs. Since airbags are vital safety features that can limit damage and save lives, a vehicle with this code should not be driven until an inspection has been performed.
The possible repairs for the B1902 trouble code are:
The B1902 code is a manufacturer specific trouble code. This means that the code has different definitions depending on the automaker. The B1902 trouble code signals a circuit error in the #1 airbag crash sensor for many cars, but a completely different problem for many other cars. It is very important that technicians pay attention to the vehicle that they are inspecting when diagnosing the B1902 code.
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