B1993 OBD-II Trouble Code: Driver Side Side-Mount Air Bag Circuit Short to Ground

Our certified mechanics come to you · Get a fair and transparent estimate upfront


Cost of diagnosing the B1993 code

B1993 is a diagnostic trouble code (DTC) for "Driver Side Side-Mount Air Bag Circuit Short to Ground". 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.

Cars Estimate* Credit towards follow-up repair Earliest Availability
Ford $154.99 $50.0
Toyota $154.99 $50.0
BMW $164.99 $50.0

*Estimates may vary by market

SCHEDULE B1993 DIAGNOSTIC Get a fair and transparent estimate upfront

B1993 code definition

When the Powertrain Control Module (PCM) receives a voltage signal from the driver's side, side mount airbag circuit that varies from the manufacturer's specifications, a B1993 trouble code can be stored. Other trouble codes to look for that the PCM could store in addition to the B1993 code include a B1992, B1994, B1995, B1996, B1997, B1998, and B1999 code.

What the B1993 code means

When the PCM detects a variance in the voltage from the driver's side side-mount air bag circuit that falls out of the range recommended by the manufacturer, a B1993 trouble code is stored and the Supplemental Restraint System (SRS) warning light illuminates. In addition to a stored code and warning light illumination, many vehicles disable the SRS system with the storage of this code.

What causes the B1993 code?

When diagnosing a B1993 trouble code, mechanics should keep in mind the most common cause, including loose, faulty, or otherwise damaged wiring, connectors, and components. In addition, a fault with the ground wire or a fault within the airbag components can cause storage of a B1993 trouble code. A loose battery connection, corroded battery cable connectors, or a bad battery can also cause this code storage.

What are the symptoms of the B1993 code?

The primary symptom of a B1993 trouble code is usually just the illumination of the SRS warning light. If the light is not working, the PCM notifies the driver via a series of audible tones that go off while driving.

How does a mechanic diagnose the B1993 code?

To diagnose a B1993 trouble code, the mechanic needs to use an appropriate OBD-II scanner and a digital multimeter with the output set to 10 mA or less. The mechanic must also perform the following steps while diagnosing the code:

  • Start by clearing the code and then retesting the system to see if that fixes the problem.

  • If the code returns, the mechanic should download the freeze frame data and any stored trouble codes.

  • Next, the mechanic should start the vehicle and test the airbag wiring while the vehicle is running. This includes shaking the wiring harness to see if there is any intermittent operation created by a possible faulty or loose wire or connector.

  • While the vehicle is running, the mechanic should test drive the vehicle to see if he can get the code to repeat during driving conditions.

  • If the code returns, the mechanic should first disconnect both battery cables before proceeding to more thoroughly inspect the wiring, connectors, or components of the wiring harness.

  • While the battery is disconnected, the mechanic should check the battery to see if it is bad, inspect the battery cable clamps for damage, and look for any corrosion on the battery cable terminal ends or on the battery posts.

  • After replacing any faulty or damaged wiring or connectors, the mechanic should also reconnect the battery cables, reprogram the airbag control module if needed, and clear the code.

  • Retest the system, and if the code returns, check the reference voltage and the ground signal at the driver's side, side mount airbag circuit with the digital multimeter.

  • If no signal is present, the mechanic should suspect a bad circuit. They should disconnect the PCM and other related control modules and check the continuity of the circuit with the battery ground.

  • The mechanic can also check the continuity between the relevant control modules and the PCM and the continuity between the PCM and the side mount airbag circuit.

  • Finally, the mechanic should clear the code, once all repairs and replacements have been made, and retest the system to see if the code returns.

Common mistakes when diagnosing the B1993 code

Mechanics often make the mistake of replacing more expensive parts, such as the side mount airbag, first without checking the wiring or connectors for looseness or damage. The result is the problem remains unfixed and the code returns.

How serious is the B1993 code?

The storage of a B1993 trouble code is very serious. When this code is stored, the vehicle often shuts down the SRS system, which could lead to injury or death in the case of an accident. You should get this code fixed as soon as possible once you are aware of it.

What repairs can fix the B1993 code?

Repairing and clearing a B1993 trouble code could be as simple as replacing a few wires, or it could require the mechanic to replace other components, such as the side mount airbag. To repair a B1993 trouble code, a mechanic needs to take the following steps:

  • Replace any faulty or damaged wiring, connectors, and components found during the initial inspection.

  • Replace the battery if it is bad.

  • Clean or replace the battery cable connectors if damaged or corroded.

  • Replace the driver's side side-mount airbag circuit if it is at fault.

  • Replace the driver's side side-mount airbag if it is bad.

  • Replace the specific airbag control module if it is not working correctly.

Additional comments for consideration regarding the B1993 code

The mechanic needs to make sure that they disconnect both battery cables before proceeding with the inspection of the driver's side side-mount airbag. They should also wait three minutes once they do disconnect the battery cables to ensure that the airbag does not deploy during the inspection.

Need help with a B1993 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.

air bags
trouble codes
B1993

No more waiting rooms! Our mechanics will come to you to diagnose and fix the B1993 code.

SCHEDULE B1993 DIAGNOSTIC
Get a $50 credit for the follow-up repair

Recent Check Engine Light is on Inspection reviews

Excellent Rating

(8600)

Rating Summary
8017
273
65
46
199
8017
273
65
46
199
 at YourMechanic

Brandon

9 years of experience
133 reviews
Brandon
9 years of experience
Ford Escort L4-2.0L - Check Engine Light is on - Nashville, Tennessee
Brandon showed up ahead of schedule, was very personable and diagnosed my problems. He also scheduled my next appointments which will be with him.
 at YourMechanic

William

23 years of experience
33 reviews
William
23 years of experience
Lexus IS250 V6-2.5L - Check Engine Light is on - Mableton, Georgia
Arrived early which was great. William was courteous, and attentive to the issue. Even though it took several attempts I'm so happy he was determined to fix it and he did!
 at YourMechanic

Dan

40 years of experience
1080 reviews
Dan
40 years of experience
Plymouth Grand Voyager - Check Engine Light is on - Lawrenceville, Georgia
Mr. Dan Barber was quite patient, courteous and quite knowledgeable. From my observation, Mr. Barber appears to be quite professional.
 at YourMechanic

Christopher

9 years of experience
120 reviews
Christopher
9 years of experience
Ford Fiesta L4-1.6L - Check Engine Light is on - Smyrna, Georgia
Chris communicated with us each step of the way up until his arrival. He listened well, was knowledgeable, and was prepared. He took the time to diagnose the problem, explained the what, why and how and provided a solution. I would definitely recommend him and will use him again.


More related articles

P0346 OBD-II Trouble Code: Camshaft Position Sensor A Circuit Range/Performance (Bank 2)
P0346 P0346 code definition The appearance of the P0346 code indicates that the PCM has detected an incorrect voltage or waveform reading from the engine bank 2 camshaft sensor A camshaft position sensor circuit. What the P0346 code means The...
P0477 OBD-II Trouble Code: Exhaust Pressure Control Valve Low
P0477 code means that the PCM has detected an abnormally low voltage reading often due to the exhaust back pressure control valve circuit.
P2764 OBD-II Trouble Code: Torque Converter Clutch Pressure Control Solenoid Control Circuit Low
P2764 means the system is receiving a faulty signal from the torque converter clutch pressure control due to failing transmission or electrical issues

Related questions

What does the Side Air Bag Off warning light mean?
The Side Air Bag Off warning light is located on the instrument panel. When the light illuminates, the passenger side air bag is temporarily deactivated. The passenger side air bag turns off when the front passenger seat is not occupied,...
Air bag light and low oil lights on
Hello there. You have a few different issues going on. The Oil Light (https://www.yourmechanic.com/article/how-to-react-when-your-oil-light-is-on-by-joyce-morse) does refer to the engine oil. When the Oil Light is on, caution should be taken when driving the vehicle, as damage can occur with the...
In a 1996 Nissan Sentra will both air bag deploy even if no passenger is present?
The Supplemental Restraint System (SRS) system in the 1996 Sentra is NOT equipped with any passenger seat sensors that could potentially determine if a passenger is actually present in the vehicle, let alone that passenger's weight. Consequently, if the SRS...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com