AU
B160A

DTC B160A indicates the driver front airbag (DAB) ignition circuit resistance is 0 ohms, representing a short circuit — Seal U

Safety System

DTC B160A indicates the driver front airbag (DAB) ignition circuit resistance is 0 ohms, representing a short circuit.

Normally, the airbag squib has a standard resistance of 2-5 ohms.

When the SRS ECU detects circuit resistance near 0 Ω, it identifies a short to ground, short to power, or internal short in the airbag module.

This safety-critical fault prevents normal airbag deployment during a collision or causes accidental deployment.

A 0-ohm resistance typically indicates an internal ribbon cable short in the clock spring (spiral cable), damaged harness insulation shorting to ground, or an internal igniter short within the airbag module.

5
Cases Logged
5
Causes
Likely Causes — Seal U
  • 1Short circuit caused by a worn or broken internal flat cable in the clock spring (spiral cable / Clock Spring): Long-term steering wheel rotation repeatedly bends the internal ribbon cable at limit positions. This damages the insulation or breaks the conductor, causing a short to ground. This is the most common root cause of this fault code.
  • 2Airbag module internal igniter short circuit: The resistance wire in the airbag igniter cartridge shorts to the housing, or a broken internal bridgewire causes direct contact between the two terminals.
  • 3Harness damage or short to ground: Chafing, crushing, or rodent bites damage the harness insulation between the SRS ECU and the clock spring (especially near the steering column), causing a short to the vehicle body metal.
  • 4Connector water ingress or terminal short circuit: Water ingress, oxidation, or deformation of the driver-side airbag connector (G10) or clock spring connector causes a short circuit between terminals.
  • 5SRS ECU internal drive circuit fault: A damaged ECU internal monitoring circuit or driver chip triggers a false short circuit fault (relatively uncommon; consider only after ruling out the preceding mechanical faults).
What To Do
  • 1
    Safety preparation: Switch the vehicle OFF, disconnect the battery negative terminal, and wait at least 90 seconds to fully discharge the SRS system backup power supply and prevent accidental airbag deployment during repair.
  • 2
    Fault Confirmation: Connect the BYD dedicated diagnostic tool (VDS or ED400), enter the SRS system to read the fault codes, confirm B160A is a Current DTC, and record the freeze frame data.
  • 3
    Visual inspection: Check driver airbag connector G10 under the steering wheel for looseness, backed-out pins, water ingress, or oxidation; check the clock spring housing for damage or burn marks.
  • 4
    Circuit isolation test: Disconnect the clock spring from the airbag module. Use the dedicated airbag system tester (or an alternative setup with a 2.2kΩ resistor in series) to measure the resistance on the wiring harness side and determine if the short circuit occurs before or after the clock spring.
  • 5
    Clock spring inspection: Remove the steering wheel (use a steering wheel puller; do not strike forcefully). Remove the clock spring and measure the resistance between its pins and to ground. Rotate the steering shaft to simulate different steering angles and observe whether the resistance remains at 0Ω or is unstable.
  • 6
    Harness continuity test: If the clock spring is normal, measure the harness between the SRS ECU connector and the clock spring. Check for a short to ground, focusing on the harness sleeve near the steering column.
  • 7
    Component replacement: Replace the confirmed faulty clock spring (center and lock it before installation, and align the steering wheel marks) or the airbag module. Never use a multimeter to directly measure the airbag inflator resistance.
  • 8
    System reset and verification: Reconnect all connectors, connect the battery, turn the ignition switch to the ON position, use the diagnostic tool to clear the fault codes, perform the SRS system self-test procedure, and confirm the airbag warning light turns off and the system has no fault codes.
Real-World Cases
BYD DTC AI AnalysisFrom Chinese market (translated)

Internal short circuit in BYD S6 clock spring caused DTC B160A

✓
A 2015 BYD S6 had the airbag warning light on. The diagnostic tool read code B160A-00 (driver front airbag resistance 0). The vehicle had no accident history, but the steering wheel had recently been removed and modified. After disconnecting the battery, the technician unplugged the driver airbag connector and measured nearly 0Ω between the harness terminals, confirming a short. Inspection found the clock spring's internal ribbon cable worn from long-term rotation, causing a short at certain steering angles. The technician fitted a genuine replacement clock spring (aligning the marks during installation), cleared the fault codes, and the system returned to normal.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

BYD Song DM clock spring terminals oxidised, horn inoperative

✓
The airbag warning light on a BYD Song DM illuminated suddenly while driving, and the horn became intermittent. Diagnostics showed DTC B160A-00. Since the horn and airbag share the clock spring, this pointed to an internal clock spring fault. Inspection revealed oxidation on the G10 connector terminals; the internal flat cable showed unstable resistance when rotated, indicating an intermittent short circuit. Cleaning the terminals and replacing the clock spring assembly resolved the fault. Repair tip: Make sure the new clock spring is centered and locked before installation, then release the lock after installation.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

BYD Qin Pro clock spring damaged after accident repair

✓
A BYD Qin Pro came in with the airbag warning light on after front-end collision repairs. Retrieved DTC B160A-00. Previous repairs had involved steering wheel removal and multifunction button replacement. Found the driver airbag connector not fully seated; the locking tab was not completely engaged. Reseated the connector, but the fault persisted. Further testing found an internal short in the clock spring—resistance measured 0 ohms. Upon inquiry, learned that the steering wheel had been turned improperly during the collision repairs, overwinding the clock spring's internal coil and causing it to fail. Replaced the clock spring. Using a diagnostic tool, configured and coded the SRS, then performed sensor calibration. Fault cleared.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

BYD S7 clock spring worn after long-term use

✓
A BYD S7 used for 5 years and driven 80,000 km had its airbag warning light change from intermittent flashing to constantly on, storing DTC B160A-00. The driver-side airbag harness from the G10 connector to the clock spring was normal, and the airbag module pins showed no faults. A close look at the clock spring found that long-term use had worn and fractured the internal flat cable at the steering limit positions, causing a short circuit (0 ohms) at certain angles. Replaced the clock spring with an OEM unit. During the repair, centred the steering wheel and made alignment marks. After reconnecting the battery, ran a system self-test and the warning light went out.
Original source ↗
BYD DTC AI AnalysisFrom Chinese market (translated)

Water ingress into the BYD Tang DM connector caused a short circuit.

✓
A BYD Tang DM's airbag warning light came on after driving through water. The diagnostic scanner reported DTC B160A-00. Inspection found water inside the driver-side airbag connector G10. Water traces between the terminals caused a short circuit; resistance measured close to 0Ω. Dried the connector with compressed air, cleaned terminal oxides, and applied special conductive grease. Also checked the clock spring sealing condition and confirmed no internal water ingress. Reconnected the connector, cleared the fault code, and resolved the fault. Recommend checking the vehicle's water sealing after wading and replacing waterproof seal rings if necessary.
Other Seal U 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.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.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.B110AThis DTC indicates interrupted CAN bus communication or abnormal data between the air conditioning control unit (ACU) and the PM2.5 air quality sensor. The PM2.5 sensor monitors particulate concentration inside and outside the vehicle and provides the basis for purification control in the automatic air conditioning system. The ACU triggers this fault if it fails to receive a valid CAN message from the sensor within the specified period (usually 100-500 ms), if message verification fails, or if the signal frame times out. Although this fault does not affect vehicle driving safety, it disables the automatic air purification function. The air conditioning system cannot automatically switch between recirculation and fresh air modes or activate the air purification mode based on air quality. A persistent fault may restrict the thermal management strategy.
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. Sources: [1]