B1907 — Air Bag Crash Sensor #2 Ground Circuit Failure

body electrical

Is it safe to drive?

Drive with caution The car drives normally, but with the SRS light on the airbags may not deploy in a crash. Treat it as a safety-critical repair: fine to drive to the shop, not fine to ignore for months.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm B1907 is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many B0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the airbag / restraint system (SRS) for damage, corrosion, chafing or poor contact.
Subsystem check Read the SRS module with a scanner that supports airbag systems — generic OBD2 readers cannot see these codes.
Subsystem check Inspect under-seat connectors — they are often disturbed by seat movement or cleaning.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm B1907 does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for B1907 (parts and labor, USD, independent shop rates): SRS module reset or replacement: $300–$1,000; Replace a sensor or clockspring: $150–$500; Reconnect or repair SRS wiring/connectors: $80–$250. Overall, fixing B1907 usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

What does OBD2 code B1907 mean?

Air Bag Crash Sensor #2 Ground Circuit Failure (B1907): a body electrical fault affecting the airbag / restraint system (SRS). Short, gentle driving to a shop is usually possible. Most often caused by damaged wiring under seats or in the steering column, faulty impact or occupancy sensor, SRS control module fault or stored crash data.

Is it safe to drive with B1907?

The car drives normally, but with the SRS light on the airbags may not deploy in a crash. Treat it as a safety-critical repair: fine to drive to the shop, not fine to ignore for months.

How do I diagnose B1907 myself?

Start with a scan: confirm B1907, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the air bag crash sensor #2 ground circuit, and verify the suspect component against live data before buying parts.

Will B1907 clear itself?

Sometimes B1907 clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

How much does it cost to fix B1907?

SRS module reset or replacement — $300–$1,000; Replace a sensor or clockspring — $150–$500; Reconnect or repair SRS wiring/connectors — $80–$250. Exact cost depends on the root cause, your vehicle and local labor rates — a proper diagnosis is the cheapest first step.

When the powertrain control module or supplemental restraint system (SRS) control unit detects that the ground circuit feeding crash sensor number two has gone open or developed excessive resistance, it logs diagnostic trouble code B1907. This fault falls within the body electronics family of codes and indicates a problem with one of the sensors responsible for detecting impact severity and initiating airbag deployment. The module does not set this code on a single failed check—it requires multiple failed verification cycles before confirming the defect and storing the code in permanent memory.

The supplemental restraint system relies on a network of accelerometers and pressure sensors positioned throughout the vehicle structure. Crash sensor number two specifically monitors a particular zone of the vehicle and reports acceleration data to the SRS module, which uses this information along with inputs from other sensors to determine whether and when to deploy the airbags. When the ground reference for this sensor drifts outside acceptable parameters, the module loses confidence in the sensor's readings and disables the corresponding deployment circuit as a safety measure. The stored freeze frame captures engine operating conditions at the moment of failure—values such as engine speed, calculated load, coolant temperature, and vehicle velocity—which helps recreate the failure scenario during diagnosis.

Affected vehicles will typically display an airbag system disabled warning in the instrument cluster and illuminate the supplemental restraint system warning lamp. Importantly, there are no drivability symptoms associated with B1907 alone—the engine runs normally, transmission shifts normally, and the vehicle steers and brakes as expected. The only consequence is reduced crash protection. This symptom profile is common across most SRS fault codes, making code-specific diagnosis essential.

Common Symptoms of B1907

Supplemental restraint system (SRS) warning light remains illuminated
Airbag system disabled message appears in the instrument cluster
In some cases, a second related code may accompany B1907 pointing to the affected sensor or circuit
No observable changes in engine performance, braking, or handling
The disable indicator may flash intermittently before settling to a solid warning state

What Causes B1907?

Faulty or degraded crash sensor number two: The sensor itself may have failed internally, producing erratic resistance values in its ground circuit
Open or high-resistance wiring in the sensor ground circuit: Chafing, connector corrosion, or wire breakage between the sensor and module
SRS control module internal failure: The module may no longer correctly process ground reference inputs from the sensor
Stored crash data or module reset requirement: After an actual collision (even a minor one), the module may require reprogramming or replacement
Low system voltage or depleted backup capacitor: The SRS module stores backup power to deploy airbags after battery disconnection; insufficient voltage prevents proper sensor operation
Failed clockspring assembly: Though more commonly associated with driver airbag circuit codes, clockspring degradation can affect multiple SRS circuits
Disturbed under-seat wiring connectors: Seat tracks and occupant sensors in this area frequently experience connector unseating from routine movement

How to Diagnose B1907

Connect a scanner capable of reading SRS-specific codes (standard OBD2 readers often cannot access supplemental restraint system data). Confirm B1907 is present, note whether it is a hard failure or intermittent, and record all associated freeze frame information.
Review the freeze frame data to identify engine speed, calculated load, and vehicle speed at the fault moment. Attempt to reproduce these conditions during the drive cycle portion of your verification test.
Search for technical service bulletins specific to your make, model, and model year using your vehicle identification number on the manufacturer portal or NHTSA website. Some B1907 occurrences have documented factory fixes or software recalibrations.
Perform a thorough visual inspection of the wiring harness and connectors associated with crash sensor number two. Pay particular attention to areas near the front bumper, firewall, and door sills where wiring passes through body openings. Check for damaged insulation, green corrosion on terminals, and loose or unplugged connections.
Inspect all under-seat SRS connectors, including seat position sensors and occupant classification system wiring. These connectors commonly become partially unseated during seat removal, floor cleaning, or cargo loading.
After clearing the code, complete a full drive cycle that includes the conditions from your freeze frame data. If B1907 returns, the fault is confirmed and component-level diagnosis continues; if it does not return, the issue was likely a temporary voltage fluctuation or connector disturbance.

Repair Options for B1907

SRS module service: Some vehicles permit module reset through specialized diagnostic equipment that clears stored crash data and relearns sensor baselines. If the module itself has failed, replacement is required. Module replacement includes programming to the vehicle.

Crash sensor replacement: Crash sensor number two can be individually sourced and replaced. Labor involves access to the sensor location, which varies by vehicle but is often in the front bumper, A-pillar, or door sill area.

Clockspring replacement: Required if diagnostic testing reveals the clockspring (which maintains electrical continuity through the steering column rotation path) has failed.

Wiring repair or connector service: Damaged wires can be spliced and sealed. Corroded terminals can be cleaned or replaced with new connector halves.

How Much Does It Cost to Fix B1907?

Independent shop labor rates typically range from $80 to $150 per hour depending on region. SRS module reset or replacement runs $300 to $1,000 including parts and programming. Crash sensor or clockspring replacement costs $150 to $500 depending on the component and labor access difficulty. Wiring harness repair or connector replacement costs $80 to $250. The wide range reflects the difference between a simple connector reseat and full module replacement. An accurate diagnosis before purchasing parts is strongly recommended—the most expensive repair is rarely the first step.

Can You Drive with B1907?

B1907 carries a caution severity rating. The vehicle remains mechanically operational and can be driven to a repair facility without risk of breakdown. However, the illuminated airbag warning indicates that one or more deployment circuits are disabled. In a collision, the affected sensor zone may not trigger airbag deployment as designed. This is a safety-critical system—schedule repair promptly and avoid long-distance highway driving until the system is restored.