AU
B167C00

DTC B167C00 indicates the Right Rear Side Impact Sensor in the Supplemental Restraint System (SRS) detects an internal functional fault — Atto 8

Safety System

DTC B167C00 indicates the Right Rear Side Impact Sensor in the Supplemental Restraint System (SRS) detects an internal functional fault.

The sensor typically mounts in the vehicle C-pillar or right rear quarter panel area to monitor collision acceleration on the right rear side.

The SRS control module sets this fault code when the sensor experiences an internal circuit fault, communication interruption, or abnormal signal.

This fault may prevent the right rear side airbag or curtain airbag from deploying normally during a side impact, severely compromising passive safety performance.

It does not directly affect normal vehicle driving functions.

The B167C00 fault code on the Atto 8 indicates a medium severity internal malfunction in the right rear side impact sensor, which monitors collision forces near the C-pillar. This SRS fault may prevent the right side or curtain airbag from deploying during a crash. Common causes include internal circuit failure or wiring connector issues. Visiting an authorised dealer is recommended. Typical repair cost data is available from 4 documented cases.
4
Cases Logged
5
Causes
Likely Causes — Atto 8
  • 1Damage or degradation of the sensor body internal circuit causes abnormal signal output.
  • 2Poor contact, oxidation, or terminal back-out at the sensor wiring harness connector. Repeated bending easily damages the wiring harness inside the C-pillar trim.
  • 3Improper sensor installation position or insufficient retaining bolt torque after rear-end accident repairs reduces sensor detection sensitivity.
  • 4Open circuit, short to ground, or short to power in the communication line between the SRS control module and the sensor.
  • 5Incorrect sensor configuration or calibration (sensor calibration procedure not performed after part replacement).
What To Do
  • 1
    Use the BYD VDS diagnostic tool to read and confirm the DTC status. Check for related DTCs (such as B167B11, B167D00). Record the freeze frame data, attempt to clear the DTC, and observe if the fault is intermittent.
  • 2
    Remove the right rear C-pillar trim panel and inspect the side impact sensor for physical damage, cracks, or water stains. Verify the correct sensor installation direction and confirm the fastening torque meets the standard (usually 8-10 N·m).
  • 3
    Disconnect the battery negative terminal and wait 3 minutes. Unplug the sensor connector and check the pins for oxidation or backing out. Measure the wiring harness side: with the ignition switch ON, the reference voltage must be 5V, and the ground wire resistance must be less than 1Ω.
  • 4
    Use an oscilloscope to check the sensor signal waveform. The sensor normally outputs a 2.5V reference voltage when static and produces a corresponding voltage change during collision simulation. A fixed 0V or 5V output indicates an internal sensor fault.
  • 5
    Check the continuity and insulation of the communication line (usually the PWM signal line) between the SRS ECU and the sensor. Measure the wiring harness resistance; it must be less than 2Ω. Insulation resistance to ground/power must be greater than 10MΩ.
  • 6
    If testing confirms a sensor fault, replace the sensor with a genuine part (match the part number to the vehicle model; the Qin Pro series typically uses SAS-3643X0 or a newer version). After installation, perform the 'Airbag Sensor Calibration' procedure.
  • 7
    After completing the repair, use VDS to perform an SRS system self-check and confirm no fault codes. Perform a simulated crash test (using the special tool) to verify normal sensor response.
Real-World Cases
BYD DTC AI Analysis

Qin Pro DM: Worn right rear collision sensor wiring harness causing intermittent warning.

✓
Airbag warning light illuminated intermittently. DTC B167C00 stored. Inspection found the wiring harness inside the right rear C-pillar had worn insulation from repeated rear door operation, causing copper wires to intermittently short to earth. Replaced 30 cm of damaged wiring, added abrasion-resistant corrugated tubing for protection, and re-routed harness away from metal edges. Fault resolved.
BYD DTC AI Analysis

Incorrect sensor orientation after accident repair caused fault.

✓
The vehicle sustained scrape damage on the right rear. After the right rear quarter panel was replaced at an independent shop, the instrument cluster displayed a persistent airbag fault. Diagnosis found the right rear side impact sensor installed backward (arrow should point forward), causing incorrect axial sensing. Reinstalled the sensor in the correct orientation, tightened to the specified 9 N·m with a torque wrench, and performed system calibration. Fault cleared.
BYD DTC AI Analysis

Internal short circuit in sensor due to water ingress

✓
After driving through water, the airbag warning light stayed on constantly. Found current fault code B167C00. Removed and inspected the right rear sensor; found internal water ingress and corrosion. Measured resistance below 100Ω, indicating a short circuit. Cause: Aged sensor seal allowed water to penetrate via capillary action through the wiring harness during water exposure. Replaced the sensor and waterproofed the wiring harness connector (applied conductive grease and waterproof tape). Fault resolved.
BYD DTC AI Analysis

SRS control module software false alarm update case

✓
Multiple Qin Pro vehicles reported DTC B167C00. The sensors and wiring harness tested normal. A BYD technical bulletin confirmed that early SRS control module software contained false diagnostic logic. Solution: Upgrade the SRS ECU software to V2.3 or higher. The fault code does not return after the upgrade; no hardware replacement required.
Other Atto 8 Fault Codes
B110811This DTC indicates a short circuit in the air conditioning system PM2.5 air quality sensor (rapid detector). Specifically, abnormal continuity exists between the sensor power supply circuit or signal output circuit and body ground or battery positive. This causes the control module (ACU/air conditioning controller) to detect abnormal current or a voltage signal outside the valid range (typically 0V or supply voltage). The PM2.5 sensor monitors internal and external particulate concentrations, providing the data the automatic air conditioning system uses to switch between fresh air and recirculation modes. A short circuit disables the air quality monitoring function. This fault may force the air conditioning system into recirculation protection mode and trigger related thermal management system faults, as the air conditioning system acts as a key actuator in vehicle thermal management. In severe cases, the short circuit current can damage the internal sampling circuit of the air conditioning controller or overheat the wiring harness.B1109DTC B1109 indicates an open circuit in the communication line between the air conditioning system PM2.5 air quality sensor (dust concentration sensor) and the air conditioning control unit (AC ECU), or an open circuit within the sensor internal circuitry. Typically located in the air conditioning intake duct, this sensor monitors real-time PM2.5 particle concentration inside and outside the vehicle. It provides data to the automatic air conditioning system for intelligent switching between fresh air and recirculation modes and for controlling the air purification device. During an open circuit fault, the AC ECU cannot receive the air quality signal, triggering the system fail-safe mode. Symptoms typically include failure of the automatic recirculation function, abnormal air purification indicator light operation, or abnormal air quality data displayed on the air conditioning panel. Severe cases may compromise the cabin environment control strategy, but do not directly affect vehicle driving safety.B110A02DTC B110A02 indicates the thermal management master control unit (HVAC ECU) or body control module (BCM) failed to receive valid CAN data frames from the PM2.5 air quality sensor over consecutive communication cycles (typically 500ms per cycle). The sensor typically mounts at the HVAC unit air inlet or behind the glove box and transmits real-time particulate concentration data (unit: μg/m³) to the HVAC controller via the CAN bus. The fault is essentially a communication link layer timeout. Potential causes include physical layer wiring faults, sensor power supply failures, sensor internal MCU lockup, or CAN network topology damage. Although this non-critical fault does not directly affect driving safety, it disables the intelligent air purification strategy and the automatic fresh air/recirculation switching function. In extreme cases, it triggers a thermal management system degraded mode, limiting compressor power or fixing the air flap position.B110B07This fault code indicates abnormal operation of the internal air pump (sampling pump) in the PM2.5 air quality detection module. The PM2.5 detector uses the laser scattering principle to measure particulate concentration and requires a built-in air pump to draw ambient air into the detection chamber at a constant flow rate. The ECU sets this code when it detects an open or short in the air pump drive circuit, abnormal current (stall or free-running), or abnormal speed feedback. This fault causes the automatic air conditioning system to lose air quality sensing capability, preventing automatic switching between fresh air and recirculation modes. The instrument cluster air quality display may show '--' or a fixed value, but the fault does not affect the vehicle powertrain or basic air conditioning cooling and heating functions.B173CDTC B173C indicates the Supplemental Restraint System (SRS) detects the Right Second Row Side Airbag squib circuit resistance exceeds the calibrated threshold (typically >4.5Ω). This fault is an active diagnostic result of the SRS system, indicating a high-resistance condition in the circuit between the Airbag Control Unit (ACU) and the airbag module. Causes for excessive resistance include increased contact resistance, a partially broken wiring harness, terminal oxidation, or an aging squib wire inside the airbag module. This fault causes the system to mark the airbag circuit as 'unreliable', meaning the airbag may fail to deploy during a collision. The fault typically illuminates the instrument cluster airbag warning light (SRS light) continuously, and some models also sound a warning buzzer.
Common problems reported for Atto 8 →Atto 8 overview →
Data confidence: Official This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.