AU
B175111

This DTC indicates the Supplemental Restraint System (SRS) detected an abnormally low-resistance connection (short to ground) between the right rear side airbag squib circuit (typically located on the outer side of the right rear seat or inside the C-pillar trim panel) and vehicle chassis ground (GND) — Qin Plus

Safety System

This DTC indicates the Supplemental Restraint System (SRS) detected an abnormally low-resistance connection (short to ground) between the right rear side airbag squib circuit (typically located on the outer side of the right rear seat or inside the C-pillar trim panel) and vehicle chassis ground (GND).

Under normal conditions, the airbag squib circuit maintains a specific resistance (approximately 2-3Ω).

When the ACU (Airbag Control Unit) detects circuit resistance near 0Ω, it registers a short to ground.

This constitutes a critical safety fault.

The system immediately illuminates the SRS warning lamp and disables the right rear side airbag and related coordinated protection functions to prevent accidental deployment while driving or deployment failure during a collision.

The B175111 fault code on the Qin Plus indicates a high-severity SRS fault: a short to ground in the right rear side airbag squib circuit. This can disable the right rear side airbag and turn on the SRS warning light. Common causes include damaged wiring insulation near the seat or pillar trim, or water/oxidation in the SRS connector. Visit an authorised dealer for diagnosis and repair. Typical repair cost data is available.
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Cases Logged
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Causes
Likely Causes — Qin Plus
  • 1Right rear side airbag wiring harness insulation wear: Long-term chafing of the harness against the seat frame, C-pillar trim retaining clips, or door sill trim edge wears through the insulation, causing internal wires to directly contact the vehicle body metal and short to ground.
  • 2Water ingress and oxidation at the connector under the seat or B/C pillar: A blocked rear sunroof drain, poor rear windshield sealing, or water entering the right rear door sill during car washing causes the pins inside the yellow SRS connector to short circuit or short to ground.
  • 3Wiring harness fatigue from frequent seat adjustment: Frequent forward and backward sliding of the right rear seat pinches and excessively bends the airbag wiring harness at the seat rail, breaking the internal copper wire and causing a short to ground.
  • 4Improper repair procedures: Fixing screws or clips pierce the airbag wiring harness during removal and installation of the right rear seat or C-pillar interior trim panel, or during installation of floor coverings or mats, causing a short to ground.
  • 5Airbag module internal fault: Right rear side airbag igniter internal bridge wire shorted to housing (very rare; usually triggers simultaneous fault codes from other airbags).
What To Do
  • 1
    Safe power-down: Turn off the ignition, disconnect the negative battery terminal, and wait at least 90 seconds to fully discharge the SRS capacitor and prevent accidental airbag deployment.
  • 2
    Locate the component: Confirm the right rear side airbag installation position (Qin Pro series: typically inside the right rear seat outer backrest or C-pillar). Remove the right rear seat or lower C-pillar trim panel to expose the yellow SRS wiring harness connector.
  • 3
    Visual inspection: Check the wiring harness at the seat rail, C-pillar mounting point, and door sill transition for signs of pinching, cuts, or chafing; check the connector for green corrosion, water stains, or bent pins.
  • 4
    Resistance measurement: Disconnect the airbag control unit (ACU) connector. Use a multimeter to measure the resistance between the right rear side airbag circuit pins and body ground. Normal resistance is infinity (OL). Continuity indicates a short circuit.
  • 5
    Section-by-section troubleshooting: Measure wiring harness continuity in sections between the seat connector and the ACU. Use the wiggle test (measure while wiggling the harness) to locate the short circuit. If the wiring harness is normal, use the dedicated load tool substitution method to measure the airbag assembly resistance.
  • 6
    Repair procedure: If the wiring harness is damaged, strip the insulation, solder the break point, and insulate with double-layer heat-shrink tubing. Reroute the harness to avoid contact with sharp edges. If water enters the connector, thoroughly clean and dry it, then apply conductive grease. Replace the waterproof connector if necessary.
  • 7
    System verification: Restore all connections, reinstall the seat, and reconnect the battery. Use the diagnostic tool to clear the fault code. Perform an SRS system self-check. Verify B175111 does not return and the instrument cluster airbag warning light turns off. Perform a multi-directional seat adjustment test to ensure the fault does not recur.
Real-World Cases
BYD DTC AI Analysis

Right rear seat wiring harness winding mechanism internal break and short circuit

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Symptoms: SRS warning light stays on after starting the vehicle. The right rear seat had been adjusted frequently. Diagnosis found current fault code B175111. Removed and inspected the right rear seat. Found the side airbag harness wires had fatigue-fractured inside the winding mechanism (similar to a clock spring) at the junction between the seat back and cushion. The broken ends touched the metal seat frame, causing a short to ground. Repair: Replaced the right rear seat airbag harness assembly (including the winding mechanism). Re-secured the harness routing to ensure no interference throughout the full range of seat adjustment.
BYD DTC AI Analysis

Right rear door sill wiring harness connector corroded due to water ingress

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Symptoms: The SRS warning light came on after driving in heavy rain or washing the vehicle, and the right rear floor mat was damp. Diagnostics showed intermittent DTC B175111. Inspection found significant water staining and green corrosion inside the yellow SRS connector behind the right rear sill trim panel, with the connector pins showing continuity to ground. Root cause: The sunroof rear drain hose had detached, allowing water to run down the C-pillar and into the sill. Resolution: Unclogged and secured the drain hose. Removed the connector, cleaned the pins with electronic contact cleaner, dried them, applied silicone grease, and replaced the waterproof seal. Fault resolved.
BYD DTC AI Analysis

Seat rail pinched wiring harness after seat removal and refitting

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Symptoms: After replacing the right rear seat cover, the airbag warning light illuminated. Diagnostics retrieved code B175111 which would not clear. Diagnosis: The airbag wiring harness was not properly secured during the repair and got trapped between the seat rail and body. Adjusting the seat caused the metal edge to cut through the harness insulation, shorting the wire to ground. Repair: Released the seat mounting bolts and extracted the crushed harness. Cut out the damaged section, re-soldered and re-insulated the wires. Secured the airbag harness to a safe position on the seat frame using dedicated harness clips.
BYD DTC AI Analysis

Internal drive circuit fault in the airbag control module

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Symptoms: Fault persisted after ruling out the wiring harness and airbag components; or multiple airbags simultaneously reported short-to-ground faults after water ingress (e.g., B175111, B175211). Diagnosis: Disconnected the right rear airbag connector. Continuity from the harness to the ACU and insulation to ground both tested normal. Measured abnormally low resistance from the corresponding ACU pin to ground. Determined an internal ACU drive MOSFET or filter capacitor breakdown caused a short circuit. Repair: Replaced the airbag control module, performed online programming and matching (synchronised VIN, immobiliser and tyre pressure data), and completed system calibration.
Other Qin Plus Fault Codes
B1108For the BYD Song MAX (2017–2019), DTC B1108 indicates a short circuit in the PM2.5 air quality detection module (dust sensor) or its wiring harness. The sensor uses laser scattering to detect in-cabin and outside PM2.5 concentrations and transmits data to the HVAC ECU via the LIN bus or an analog signal. Short circuit conditions include: 1) Sensor power supply wire (+5V/+12V) shorted to ground 2) Signal wire shorted to power or ground 3) Short circuit in the sensor's internal photoelectric detection circuit This fault prevents the automatic climate control from switching between fresh air and recirculation based on air quality. The system enters fail-safe mode (typically forced recirculation). Severe short-circuit current can destroy the HVAC ECU sampling circuit. The system classifies this as a Level 3 severe fault and restricts vehicle operation to prevent electrical fires or controller damage. For other BYD models (such as the Qin EV, E5, and Song DM), B1108 indicates a driver-side sunload sensor fault, reflecting differences in DTC definitions across models.B110913DTC B110913 indicates an open signal circuit for the PM2.5 rapid detector (in-cabin air quality sensor). This sensor typically mounts inside the air conditioning system intake duct. It monitors in-cabin PM2.5 concentration in real time and provides data to the automatic air conditioning system for intelligent control of the air purification function. The BYD diagnostic protocol uses sub-code '13' to specifically indicate an open signal circuit. Although this fault theoretically affects a comfort feature, BYD Qin series vehicles classify it as a Level 3 (severe) fault. This classification occurs because the air conditioning system interacts with the battery thermal management system (e.g., monitoring battery cooling intake air quality). The fault can disable the automatic air conditioning mode and prevent the air purification function from operating. In extreme cases, it affects the battery compartment intake air quality assessment, triggering the 'repair immediately' strategy.B110BDTC B110B indicates a fault in the internal air pump (sampling pump) of the PM2.5 air quality detector. This pump draws cabin or outside air into the PM2.5 sensor detection chamber, enabling the laser scattering sensor to measure real-time particulate matter concentration. The air conditioning controller (or BCM) sets this DTC upon detecting an open or short circuit in the pump drive circuit, or abnormal current caused by a seized pump motor. This fault disables the "Green Clean" system, causes the instrument cluster air quality display to read abnormally or disappear, and disables the automatic fresh air/recirculation switching function. It does not affect the vehicle powertrain or core thermal management functions.B173A1ADTC B173A1A indicates the right middle-row side airbag (typically located on the side of the right second-row seat or inside the C-pillar trim panel) igniter circuit resistance measures 0 Ω. In the Supplemental Restraint System (SRS), normal airbag igniter resistance ranges between 2.0 and 5.0 Ω. A resistance of 0 Ω indicates a short to ground or a short between circuit wires, preventing the Airbag Control Unit (ACU) from establishing a normal monitoring circuit. This safety-critical fault prevents the airbag from deploying during a collision, continuously illuminates the instrument panel SRS warning lamp, and may force the entire airbag system into fail-safe mode.B173BDTC B173B indicates an abnormal electric A/C compressor speed feedback signal or a communication fault between the compressor controller and the motor. In BYD new energy models (e.g., Tang, Song, Qin, and Yuan series), this DTC belongs to the HVAC subsystem within the Body Control system and specifically involves the electric compressor closed-loop control circuit. The ECU sets this DTC when the compressor controller (IPM) fails to receive a valid pulse signal from the Hall speed sensor for more than 3 continuous seconds, or when the deviation between the detected actual speed and the target commanded speed exceeds the calibrated threshold (typically >500 rpm). This fault forces the A/C system into fail-safe mode and stops compressor operation. Symptoms include a complete lack of cooling, intermittent cooling, or a sharp decrease in cooling performance. The instrument cluster A/C warning lamp may also illuminate. Prolonged operation with this fault can degrade high-voltage system insulation or cause controller overcurrent damage.
Common problems reported for Qin Plus →Qin Plus 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.