What Does B1907 Mean?
This code indicates the Airbag Control Module (ACM) has detected a ground circuit fault in crash sensor #2, which is typically a side-impact or frontal crash sensor. The module monitors ground circuit continuity and resistance, and has detected either an open circuit, high resistance, or short to power in the ground path. This prevents the crash sensor from functioning properly and compromises the supplemental restraint system's ability to detect collisions.
Safety Warning
Not safe to drive as the airbag system is compromised and may not deploy in a crash, or could deploy unexpectedly. The airbag warning light will remain illuminated, and crash sensor #2 zone protection is disabled. Repair immediately before operating vehicle.
Common Causes
45%
Corroded, loose, or damaged ground connection at crash sensor #2 or chassis ground point
30%
Damaged wiring harness between crash sensor #2 and ACM (chafing, breaks, corrosion)
15%
Faulty crash sensor #2 internal ground circuit failure
10%
Water intrusion or corrosion in crash sensor connector causing ground circuit intermittent fault
Diagnostic Steps
1
Step 1: Perform visual inspection of crash sensor #2 (usually located in front bumper, B-pillar, or door area) and inspect connector for corrosion, bent pins, water intrusion, or physical damage. Check for accident history or recent front/side impact damage.
2
Step 2: Using a digital multimeter, check ground circuit continuity from crash sensor #2 connector (sensor disconnected) to chassis ground. Resistance should be less than 5 ohms. Also check for short to voltage (should read battery voltage with ignition on if shorted).
3
Step 3: Inspect entire wiring harness from crash sensor to ACM for chafing, pinch points, damage from previous repairs, or corrosion. Pay special attention to areas where harness passes through body panels or near moving components.
4
Step 4: Test crash sensor ground circuit resistance with sensor connected and ACM disconnected. Measure resistance between ACM connector ground pin and chassis ground (refer to wiring diagram for pin identification). Should be less than 5 ohms.
5
Step 5: If all wiring and grounds test good, substitute crash sensor #2 with known-good unit or test sensor per manufacturer specifications. Clear codes and verify repair by road testing and monitoring live data.
6
Step 6: After repairs, perform ACM self-test procedure and verify airbag warning light extinguishes. Document crash sensor resistance values and ensure all connectors are properly sealed against moisture.
Estimated Repair Cost
$150 - $650
Parts + labor, varies by vehicle and location
This code indicates the Airbag Control Module (ACM) has detected a ground circuit fault in crash sensor #2, which is typically a side-impact or frontal crash sensor. The module monitors ground circuit continuity and resistance, and has detected either an open circuit, high resistance, or short to po...
The most common cause of B1907 (Air Bag Crash Sensor #2 Ground Circuit Failure) is: Corroded, loose, or damaged ground connection at crash sensor #2 or chassis ground point
Typical repair costs for B1907 range from $150 to $650, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Not safe to drive as the airbag system is compromised and may not deploy in a crash, or could deploy unexpectedly. The airbag warning light will remain illuminated, and crash sensor #2 zone protection is disabled. Repair immediately before operating vehicle.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1907 to identify the root cause.
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Quick Info
Category
Body
System
Supplemental Restraint System (SRS/Airbag)
Difficulty
Type
Manufacturer
Recommended Tools
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