Skip the auto shop - Our mechanics make house calls

B1998 OBD-II Trouble Code: Passenger Side Side-Mount Air Bag Circuit Open

check engine light

B1998 code definition

The B1998 trouble code notes a side mount air bag circuit error on the passenger side.

What the B1998 code means

The B1998 code is a generic OBD-II trouble code that detects an air bag circuit problem in the side-mount air bag on the passenger side of the vehicle. The side mount air bag is responsible for protecting the side of the occupant in the front passenger seat, and is located on the passenger side B-pillar. If the vehicle is in a collision, the side mount air bag deploys into the passenger, to provide protection. Whenever a circuit malfunction from the side mount air bag on the passenger side is noted by the air bag control module, body control module, or powertrain control module (PCM), the B1998 trouble code may be detected.

What causes the B1998 code?

By far the most common cause of the B1998 trouble code is damaged electrical components. Usually this means shorted wires in the circuit, but blown fuses and loose connectors can also be the culprit. These damaged electrical parts may be in the side mount air bag circuit, the clockspring, or possibly the air bag control module. It is also fairly common for the B1998 code to be triggered by a defective clockspring, or a malfunctioning side mount air bag system. The code can also be stored due to a failed air bag control module, though this is rare, or due to a defective PCM or body control module, though this is very rare.

What are the symptoms of the B1998 code?

When the B1998 trouble code is detected, the air bag system will not function properly. Should an accident occur, the side mount air bag on the passenger side will almost surely fail to deploy. It is also quite possible that all of the air bags will fail, leaving the vehicle devoid of a critical safety feature. The code is often accompanied by an illuminated check engine soon Warning Light, or the air bag Warning Light.

How does a mechanic diagnose the B1998 code?

The B1998 trouble code should be diagnosed with a standard OBD-II trouble code scanner. A certified technician will use the scanner to view the freeze frame data and gather information about the code. Additional trouble codes will also be checked for, and, if detected, should be diagnosed in the order that the scanner displays them in. The codes will then be reset, the vehicle restarted, and the B1998 code checked for again. If the code is no longer present, then an intermittent issue or an erroneous detection are likely to blame.

If the code is still detected, then the mechanic will visually inspect the electrical components in the side mount air bag system, and replace any fuses, wires, or connectors that have been damaged or otherwise compromised. Next, the technician will inspect the clockspring, and the side mount air bag system. The air bag control module should then be tested.

After any replacements or repairs are made, the trouble codes will again be reset, the vehicle again restarted, and the B1998 code once more checked for. By doing this, the technician will know as soon as the issue has been fixed.

Common mistakes when diagnosing the B1998 code

The most common error when diagnosing this code is the failure to observe the OBD-II trouble code diagnosis protocol. It is highly important that mechanics abide by the protocol at all times, as it helps guarantee accurate and efficient inspections.

Side mount air bag systems and clocksprings are often inaccurately condemned, because failed electrical components were overlooked.

How serious is the B1998 code?

A vehicle with the B1998 code will still be drivable, and will not have any drivability issues. However, the air bag system will probably not function properly, which at best means the side mount air bag on the passenger side will not deploy, and at worst means all of the air bags will be inoperable. Because air bags are one of the most vital safety features that frequently save lives, the car should not be driven until an inspection and repair have been performed.

What repairs can fix the B1998 code?

Possible repairs for the B1998 trouble code are:

  • Replacement of wires, connectors, or fuses
  • Replacement of the side mount air bag system
  • Replacement of the clockspring
  • In rare cases, replacement of the air bag control module
  • In very rare cases, replacement of the PCM or body control module

Additional comments for consideration regarding the B1998 code

This code is a manufacturer specific trouble code. A manufacturer specific code is one that has a varying definition depending on the automaker. The B1998 trouble code suggests a side mount air bag circuit failure in some cars, but detects a very different body issue in many other vehicles. It is important that the mechanic always be aware of the vehicle that is being worked on when diagnosing this code.

Need help with a B1998 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
Icon-warranty_badge-02

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

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.

GET A QUOTE

More related articles

How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...


Related questions

Q: What is the side air bag cutoff system?

The side air bag cutoff system is designed to help keep the front passenger safe. This system controls whether or not the passenger side air bag is turned on, based on the height of the passenger in the seat, and...

Q: Intake maifold runner control is stuck open

Hello, thanks for writing in about your 2001 Mazda Miata. Due to this trouble code, the intake manifold runner control will need to be replaced. If this is not done you can cause serious damage to your car. If you...

Q: EML light on and caution light with arrow around came on the car, what should I do?

The warning lights mean that the vehicle's computer has detected a fault in the engine management system and/or engine controls which includes a lot of sensors and other devices. If the vehicle has not entered "limp mode" (reduced performance), is...