B1907

Code

Other B — Body

Air Bag Crash Sensor #2 Ground Circuit Failure

Brand: Other

Type: B — Body

Views: UK: 19 EN: 35 RU: 23

AI status

Completed

ready

Completed 100%

Page language: EN

Causes

Open or high-resistance ground conductor for crash sensor #2
Corroded, damaged, or loose ground connection at sensor or chassis
Poor connector pin contact, bent pins or terminal corrosion
Water intrusion or contamination in connector
Damaged wiring harness (pinch, chafe, rodent damage)
Faulty crash sensor

Symptoms

Airbag (SRS) warning lamp illuminated on instrument panel
Possible disablement of related airbag(s) or safety restraint functions
Diagnostic trouble code B1907 stored in airbag/occupant restraint module
Occasional or continuous SRS lamp depending on fault intermittency

What to check

Read and record all SRS codes and freeze frame data with a capable scanner
Visual inspection of crash sensor #2 connector, wiring, and ground point
Check for evidence of water intrusion, corrosion, or physical damage
Verify battery voltage and stable power supply to module before testing
Follow manufacturer procedure to disable SRS power (disconnect battery and wait recommended time) before handling connectors

Signal parameters

Ground continuity from sensor ground terminal to chassis ground: should be low (typically
Voltage on related supply lines: nominal vehicle battery voltage present when key on (for sensors that are powered)
Resistance across sensor ground to module ground: low and stable; high or variable resistance indicates a problem
No short to battery voltage on the ground circuit

Diagnostic algorithm

Read and record SRS codes and any additional related codes. Note freeze frame/occurrence conditions.
Follow vehicle manufacturer's procedure to disable the SRS (disconnect battery and wait specified time) before touching connectors or sensors.
Perform a careful visual inspection of crash sensor #2, its mounting, connector, and harness for damage, corrosion, or signs of water ingress.
With ignition off and battery disconnected, disconnect the sensor connector and inspect terminals for corrosion, bent pins or pushed-out terminals. Repair or replace connector as necessary.
Check continuity between the sensor ground terminal and a known good chassis ground with a multimeter. Expect very low resistance (typically
With connector disconnected, check for unintended short to battery voltage on the ground circuit. Repair any short to voltage.
If wiring and connector check good, reconnect and perform wiggle tests while monitoring live data or SRS lamp (if supported) to detect intermittent faults.
If wiring and ground are confirmed good, swap or bench-test the crash sensor if a known-good unit or follow manufacturer bench-test procedure. Replace sensor only if testing indicates internal fault.
If sensor replacement does not clear the code, suspect the airbag control module ground/driver or module fault and follow module-level diagnostics (may require manufacturer-level tools and procedures).
After repairs, clear codes, reconnect battery, and perform diagnostic verification drive or SRS self-check per manufacturer instructions.
Safety note: Always follow manufacturer service manual SRS disable/enable procedures and use appropriate PPE. Airbag system work can be hazardous if handled improperly.

Likely causes

Loose or corroded ground at sensor mounting point
Broken or chafed ground wire between sensor and chassis/ECU
Connector terminal corrosion or bent pin
Sensor itself has an internal ground fault
Poor chassis ground at nearby mounting bolt

Fault status

⚠️ Status

Air Bag Crash Sensor #2 ground circuit failure detected. The airbag control module has logged an open/high resistance or short condition on the sensor ground, disabling the sensor until repaired.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 0.5-2.0 hours