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B1928 OBD-II Trouble Code: Air Bag Safing Sensor Output Circuit Failure

diagnostic check engine light

B1928 definition

A B1928 trouble code is related to a vehicle’s air bag safing sensor which protects the supplemental restraint system (SRS) from deploying due to an electrical short.

What the B1928 code means

B1928 is a manufacturer specific OBD-II body code for a circuit failure within the air bag safing sensor. This verifies the force needed to deploy the air bags, serving as a failsafe from accidental deployment. When a B1928 is triggered, it means the sensor circuit has failed to be read during the vehicle’s self-test at startup.

What causes the B1928 code?

The most common causes for a B1928 are:

  • Faulty wiring to or from the air bag safing sensor
  • Faulty air bag safing sensor
  • Faulty battery voltage, resistance, or connection
  • Faulty charging system, i.e. faulty alternator
  • Faulty engine control unit (ECU).

What are the symptoms of the B1928 code?

Most drivers will not notice any different driving characteristics other than a check engine light and or air bag light. If the vehicle is involved in an accident, it’s highly probable the air bags will not deploy.

How does a mechanic diagnose the B1928 code?

Your mechanic first rule out the possibility of an intermittent code caused from a bad battery or battery connection. This will typically involve a couple of self-tests which are conducted when the key is turned to the ‘on’ position.

However, if the code returns after all of this, your mechanic will test the air bag safing sensor using a digital volt meter. If it fails, the sensor will be replaced. If it doesn’t though, your mechanic will test the circuit wiring with to try and pinpoint the source of the fault. Any damaged wiring or connectors will be cleaned, repaired, or replaced.

Common mistakes when diagnosing the B1928 code

It’s important to remember all B1xxx codes are manufacturer specific, so using a professional OBD-II scanner will help eliminate any issues around make and model confusion. Like any air bag code, it’s important to be as cost effective in repairs as possible, starting with simple troubleshooting first before the safing sensor is replaced.

How serious is the B1928 code?

If a B1928 is present, chances are high your entire air bag system will be disabled. This makes repairs important to ensure the safety of occupants.

What repairs can fix the B1928 code?

The most common repairs for a B1928 are as follows:

Additional comments for consideration regarding the B1928 code

A B1928 will likely be found in a Ford, Mercury, Lincoln, or Mazda vehicle. Any work that needs to be conducted on a vehicle’s SRS should be handled by a trained professional. The air bag could unexpectedly deploy while working to fix a B1928.

Need help with a B1928 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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