Skip the auto shop - Our mechanics make house calls

B1937 OBD-II Trouble Code: Air Bag Passenger Pressure Switch Circuit

diagnostic check engine light

B1937 code definition

The B1937 code is manufacturer-specific body code related to air bags. In this case, it means that the engine control module (ECM) has detected a fault with the passenger-side air bag.

What the B1937 code means

A code B1937 will be stored when the ECM has detected an open voltage signal from the passenger-side air bag pressure switch.

What causes the B1937 code?

Several problems may cause a B1937 code including:

  • Clock spring malfunction
  • Open circuit to passenger-side air bag pressure switch
  • Damaged or defective passenger-side air bag pressure switch
  • Passenger-side air bag module malfunction
  • SAS control module malfunction

What are the symptoms of the B1937 code?

Symptoms of a B1937 code may include:

  • Check engine light may illuminate
  • Air bag light may incorrectly illuminate
  • Air bag light may flash
  • Passenger side air bag may not inflate during a crash
  • There may be no symptoms other than a stored B1937 code

How does a mechanic diagnose the B1937 code?

A mechanic may use several methods to diagnose a B1937 trouble code, including:

  • Utilize an OBD-II scanner to check for a stored B1937 trouble code
  • Inspect the driver-side air bag module connector
  • Inspect the clock spring
  • Inspect the wiring harness between the SAS control module and clock spring for short to the power supply
  • Inspect the passenger-side air bag pressure switch
  • Inspect passenger-side air bag module
  • Perform SAS control module DTC inspection

Common mistakes when diagnosing the B1937 code

Detection conditions are for understanding the DTC outline before performing an inspection. Performing an inspection according to only the detection conditions may cause injury due to an operating error, or damage the system. When performing an inspection, it is recommended to always follow the inspection procedure.

How serious is the B1937 code?

Because a vehicle’s safe driving operation can be impacted due to faults that store a B1937 code, this code is considered a potentially serious code. When this code appears, it is recommended to immediately take your vehicle to your local service center or mechanic for repair and diagnosis.

What repairs can fix the B1937 code?

Several repairs can fix a B1937 trouble code and include:

  • Clock spring repair or replacement

  • Replace damaged or defective wiring harness between SAS control module and clock spring

  • Passenger-side airbag module repair or replacement

  • Passenger-side air bag pressure switch repair or replacement

  • SAS control module repair or replacement

Additional information related to a B1937 code

Handling the air bag system components improperly can accidentally deploy the air bag modules and pre-tensioner seat belts, which can seriously injure you and those around you. Always be sure to read the service warnings and cautions before handling the air bag system components. Anything related to air bag repairs can be both difficult and dangerous, and is often best left to professionals for diagnosis and repair. If making any repairs at home, take care with the air bags when removed from the vehicle.

In addition, a technical service bulletin (TSB) may be related to the B1937 trouble code, so it is always recommended to check and see what bulletins may be associated with a particular code prior to diagnosis and repair.

Need help with a B1937 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

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.


Post a question and get free advice from our certified mechanics.


More related articles

P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222 code means The manufacturer specifies a range of acceptable voltage to be produced from the throttle position...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Buy Fuel Treatments
Adding a fuel additive to your gas tank when you fill up is one way to clean vital engine parts of deposits, improve the performance of your engine,...

Related questions

Q: seems to be stuck in 2nd or 1st cant tell

Here are a few things to check next: With a fully charged battery, test the voltage on the ERLS fuse, Key On Engine Off (KOEO) and the transmission connector connected. If the voltage is low at the...

Q: Are Code Readers and Scan Tools Different?

There are differences and similarities between code readers and scan tools. With the advent of the vehicle on board diagnostic system (OBD) there have been many different makers of scan tools and code readers. The code readers were the first...

Q: My car cut off on the highway and wont start back up.

Good question. PO443 Code is an HVAC code. To your question, no. When a mechanic hears that a car shut off while driving it is because the alternator quit working. Your battery however, may be dead too. You can take...