B1667-00

DTC B1667-00 indicates the airbag control unit (SRS ECU) detects a short to body ground in the signal circuit of the left side impact sensor (typically installed inside the left B-pillar reinforcement panel) — Atto 3

Safety System

DTC B1667-00 indicates the airbag control unit (SRS ECU) detects a short to body ground in the signal circuit of the left side impact sensor (typically installed inside the left B-pillar reinforcement panel).

This sensor is typically a MEMS capacitive or piezoelectric accelerometer.

During normal operation, it returns a bias resistance of approximately 2.1-2.9 kΩ and a signal voltage of approximately 2.5 V to the ECU.

When wiring harness insulation breaks, water enters the connector, or the sensor shorts internally, the ECU detects a continuous voltage signal below 0.5 V (short-to-ground threshold) and triggers this DTC.

This fault disables the trigger threshold determination for the left side airbag and curtain airbag.

During a side collision, the airbags may fail to deploy promptly, or signal interference during normal driving may cause unintended deployment.

This is a highest-level safety fault.

4
Cases Logged
BYD DTC AI AnalysisFrom Chinese market (translated)

Poor connector contact damaged the sensor on BYD Qin Pro DM

The airbag warning light on the instrument panel stayed on. Read DTC B1667-00. Inspection revealed the vehicle had recently undergone left door sheet metal and paint repair. Removing the B-pillar trim during that work left the left side impact sensor connector not fully seated. Reconnecting it cleared the fault temporarily, but it returned the next day. Further measurement showed the sensor's internal resistance had abnormally dropped to 1.2 kΩ (standard 2.3 kΩ). We determined the loose connector caused an intermittent short circuit; long-term poor contact overheated and damaged the sensor's internal circuit. Replaced the left side impact sensor (part number: BYD-3636010), installing it on the B-pillar reinforcement plate at the specified torque of 8 N·m. Fault completely resolved.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

BYD Song Plus EV door sill wiring harness damaged, short to ground

After turning the ignition on, the airbag warning light stayed on. The scan showed DTC B1667-00. The data stream showed the left collision sensor voltage signal was 0V (normal 2.5V). I disconnected the sensor connector inside the left B-pillar and measured terminal KG10-12 at the harness side. Resistance to ground was less than 1Ω, confirming a short to ground. I traced the harness and found a retaining clip had compressed the wiring inside the left sill trim, damaging the insulation and exposing the copper wire to the body. Repair: I re-wrapped the damaged harness with double-layer heat shrink tubing for insulation, rerouted the harness to avoid the clip, and cleared the fault codes. The SRS system returned to normal.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

BYD Han EV connector terminal pin backed out causing intermittent short circuit

The airbag warning light came on intermittently and sometimes went out automatically. The scan tool retrieved historical DTC B1667-00 and current DTC B1666-00 (open circuit), indicating an intermittent fault. Inspection found minor damage to the left crash sensor connector latch. Wiggling the wiring harness caused resistance between terminals KG10-12 and K05(A)-2 to fluctuate between 0.5Ω and infinity. The backed-out terminal pin caused an intermittent short to ground. Replaced the left crash sensor harness connector assembly, ensured correct terminal spring tension, fully seated the connector, and locked the latch. Road-tested over rough surfaces; the fault did not reoccur.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

Incorrect sensor installation after accident repair on a BYD Destroyer 05

After a left side collision, an outside repair shop replaced the left front door and B-pillar trim. Following the repair, the airbag warning light stayed on and DTC B1667-00 could not be cleared. Inspection found the left side impact sensor was the old unit removed during the accident. It had visible cracks but had not been replaced; resistance measured 0Ω (internal short). Further inspection revealed slight deformation at the B-pillar inner panel mounting point, causing the sensor installation angle to exceed 5° (workshop manual requires ±5°). The mounting bolt torque was excessive (measured 15 N·m, standard 8 N·m), which cracked the sensor housing. Solution: Straightened and repaired the B-pillar inner panel mounting surface. Replaced the sensor and installed it to standard torque and orientation. Fault resolved.
Original source ↗
Data confidence: Community This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.