B167711 is a BYD Supplemental Restraint System (SRS) diagnostic code indicating a short to ground in the left rear side impact sensor signal circuit — Seal 6 EV
B167711 is a BYD Supplemental Restraint System (SRS) diagnostic code indicating a short to ground in the left rear side impact sensor signal circuit.
This sensor typically mounts in the left B-pillar or C-pillar area.
It detects acceleration changes during a side impact and provides a collision severity signal to the Airbag Control Unit (ACU).
A short to ground indicates insulation failure between the sensor signal wire (SIG) or power wire (VB) and the vehicle body ground (GND), dropping the resistance below the normal threshold (typically <5Ω).
This fault prevents the ACU from receiving the collision signal, triggers the system fail-safe mechanism, disables deployment of the left rear side airbag and side curtain airbag, and illuminates the airbag warning light.
During a severe collision, the affected airbags may fail to inflate, posing a severe safety hazard.
- 1Wiring harness physical damage: Long-term vibration, compression, or chafing damages the sensor wiring harness insulation inside the left rear side trim panel, below the B-pillar, or near the seat rail, causing contact with body metal and creating a short to ground.
- 2Internal sensor fault: Breakdown of the collision sensor internal IC circuit, filter capacitor, or Zener diode causes an internal short circuit between the signal and ground terminals, commonly due to sensor aging or severe vibration.
- 3Connector water ingress and corrosion: Vehicle wading, direct high-pressure washing, or aging seals allow water to seep into the left rear side panel. This oxidizes and electrolytically corrodes the sensor connector pins (usually located below the B-pillar or inside the sill beam), forming a short circuit path.
- 4Improper repair work: During left rear side accident repairs, window regulator repairs, or audio modifications, an improperly secured wiring harness allows screws or clips to crush the insulation, or an incompletely inserted connector bends the terminal against the metal frame.
- 5Internal fault in the SRS control unit: A short circuit in the filter capacitor of the ACU internal signal sampling circuit or a damaged AD converter falsely indicates an external sensor short to ground (relatively uncommon, but requires inspection).
- 1Safety preparation: Park the vehicle on level ground, turn the ignition switch to OFF, disconnect the 12V battery negative terminal, and wait at least 90 seconds to fully discharge the SRS capacitor and prevent accidental airbag deployment.
- 2Fault confirmation: Use the BYD VDS2000/VDS3000 diagnostic tool to access the SRS system, read DTC B167711 to confirm the fault is current (Active), and record the freeze frame data (ambient temperature and vehicle status).
- 3Visual inspection: Remove the left B-pillar lower trim panel and the left rear door sill trim panel. Inspect the left rear side impact sensor (usually marked 'SRS SIDE SENSOR') for physical damage, cracks, or burn marks.
- 4Circuit measurement: Disconnect the sensor connector. Use a multimeter to measure the resistance to ground for each terminal on the wiring harness side: the power wire (+B) to ground must be infinite, and the signal wire (SIG) to ground must be >1MΩ. If the signal wire resistance to ground is <5Ω, inspect the circuit along the wiring harness to the SRS control unit (usually located under the center console).
- 5Sensor test: Remove the sensor and measure the resistance between its terminals. The resistance between power and ground should be a fixed value (usually several hundred ohms to several kΩ, depending on the model), and the resistance between signal and ground should be a specified value. Replace the sensor if the signal terminal has continuity to ground.
- 6Wiring harness repair: Carefully inspect the protective corrugated conduit where the wiring harness passes through sheet metal holes and seat rail mounting points. Repair any damaged insulation (using heat-shrink tubing or electrical tape) and re-secure the harness to prevent contact with sharp edges.
- 7Component replacement: If inspection confirms an internal short circuit, replace the left rear side impact sensor (Note: Use the same part model; sensors for different vehicle models have different sensitivity curves). During installation, ensure the arrow points toward the front of the vehicle (impact direction).
- 8System reset: Reconnect all connectors, reconnect the battery negative terminal, use the diagnostic tool to clear the fault code, perform the 'SRS system self-check' and 'sensor calibration' (if available), and confirm B167711 does not return and the airbag warning light turns off.
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