B1935 code definition
The B1935 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 air bag inflator showing a low circuit resistance.
What the B1935 code means
A code B1935 will be stored when the ECM has received a voltage signal lower than preset variance thresholds.
The air bag diagnostic monitor and air bag connector utilize metal spring clips, which act as shorting bars and are built into the plastic, hardshell connectors. When the ignition switch is in the “on” position, the air bag diagnostic monitor will run checks on the resistance of the driver and passenger air bag circuits.
If the passenger air bag circuit sends a low voltage signal to the air bag diagnostic monitor, the monitor will report an error or fault to the ECM and a B1935 code may be stored.
What causes the B1935 code?
Several problems may cause a B1935 code including:
- Damaged or defective wiring and related connectors
- Short circuit in passenger side air bag module
- Damaged or defective clockspring
- Damaged or poorly mated air bag connector
- Damaged or poorly mater air bag diagnostic monitor harness connector
- Damaged or worn shorting bar
What are the symptoms of the B1935 code?
Symptoms of a B1935 code may include:
- Check engine light may illuminate
- Air bag light may incorrectly illuminate
- Air bag light may flash
- Air bags may not inflate during a crash
- There may be no symptoms other than a stored B1935 code
How does a mechanic diagnose the B1935 code?
A mechanic may use several methods to diagnose a B1935 trouble code, including:
- Utilize an OBD-II scanner to check for a stored B1935 trouble code
- Utilize an ohmmeter to check for resistance to the passenger air bag inflator circuit
- Check for damaged or defective shorting bars
- Check circuits 607 and 616 for continuity
Common mistakes when diagnosing the B1935 code
A common mistake when diagnosing the B1935 code is to assume the module is damaged or defective, when the problem could be open or shorted circuits. It is recommended to repair or replace damaged or defective wiring and rescan your system before proceeding with more involved repairs.
How serious is the B1935 code?
Because a vehicle’s safe driving operation most likely will be impacted due to faults that store a B1935 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 B1935 code?
Several repairs can fix a B1935 trouble code and include:
- Disconnect the battery immediately and wait a few minutes before proceeding
- Repair or replace damaged wires, connectors, and related electrical components
- Clean any corroded or dirty connections to ensure continuity in circuitry
- Repair or replace damaged or defective shorting bars
- Repair or replace damaged or defective passenger side air bag module
- Clear all codes, test-drive the vehicle, and rescan to see if any codes reappear
Additional information related to a B1935 code
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 and be sure to use extreme caution when reinstalling spacers to ensure correct installation.
Need help with a B1935 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.
This article originally appeared on YourMechanic.com as B1935 OBD-II Trouble Code: Air Bag Passenger Inflator Circuit Resistance Low on Squib and was authored by Parker Hill.