AU
B16E0-00

DTC B16E0-00 indicates a short to ground in the Left Rear Impact Sensor signal circuit within the Supplemental Restraint System (SRS) — Atto 3

Safety System

DTC B16E0-00 indicates a short to ground in the Left Rear Impact Sensor signal circuit within the Supplemental Restraint System (SRS).

This sensor typically mounts in the left rear quarter panel or C-pillar area to monitor collision acceleration at the left rear of the vehicle.

A short to ground indicates abnormal continuity (resistance below the normal range) between the sensor power wire, signal wire, or shield and the vehicle body metal frame.

This causes the SRS control module to receive a continuous low-level signal.

This fault forces the SRS into fail-safe mode and may cause the following: 1) The left rear side airbag/curtain airbag fails to deploy during an actual collision. 2) The system misinterprets the fault as a collision and inadvertently deploys the airbag. 3) Entire SRS functionality restricts, severely compromising passive safety performance.

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Cases Logged
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Causes
Likely Causes — Atto 3
  • 1Worn or crushed wiring harness inside the left rear side panel: Prolonged driving on rough roads causes the wiring harness to rub against metal edges, damaging the insulation and shorting the signal wire to ground.
  • 2Sensor connector water ingress and corrosion: Car washing, wading, or poor sealing causes a short circuit between connector terminals, forming a path to ground.
  • 3Rear crash sensor internal fault: Damaged internal electronic components cause a short circuit between the power supply and ground terminals.
  • 4Improper wiring harness securing after collision repair: Failure to route the wiring harness along the standard path during left rear collision repairs caused the seat bracket or interior trim panel screws to pinch the harness.
  • 5SRS control module internal short circuit: A fault in the internal signal processing circuit causes the left rear sensor channel to short to ground.
What To Do
  • 1
    Safety preparation: Disconnect the 12V battery negative terminal. Wait at least 90 seconds for the SRS system capacitor to discharge. Wear an anti-static wrist strap.
  • 2
    Visual inspection: Remove the left C-pillar trim panel and the left side of the rear bumper. Inspect the left rear crash sensor (usually numbered Y3) for physical damage, and check the connector for looseness, water ingress, or corrosion.
  • 3
    Circuit continuity test: Set the multimeter to the resistance setting. Disconnect the sensor connector and the SRS module connector. Measure the resistance between the harness-side signal pin (usually corresponding to the pin in the scan tool data stream) and body ground. The normal reading is infinity (OL). A reading of 0-5 Ω confirms a short to ground.
  • 4
    Section-by-section troubleshooting: Follow the left rear quarter panel harness routing (passing under the left rear door frame seal to the floor harness). Gradually open the corrugated conduit to inspect the harness insulation. Focus on contact points with the seat rail, seat belt anchor bolt, and rear fender inner liner.
  • 5
    Insulation repair or replacement: If the wiring harness is damaged, apply a double layer of heat-shrink tubing or waterproof tape. If the sensor fails, install an OEM left rear crash sensor (part number usually starts with 5A-). Tighten to 8-10 N·m.
  • 6
    System verification: Reconnect all connectors and restore power. Use VDS or Launch X431 to clear the fault code. Perform an SRS system self-test. Read the data stream to confirm the left rear sensor voltage signal changes normally within the 0.5-4.5V range upon impact. Perform a simulated collision test (lightly tap the sensor mounting location) to observe the data stream changes.
Real-World Cases
BYD DTC AI Analysis

BYD Qin EV300 left rear impact sensor short circuit after wading

✓
After driving through water about 30 cm deep, the airbag warning light on the instrument panel stayed on. Read fault code B16E0-00. Removed the left rear sill trim panel and found water inside the left rear impact sensor connector. Water caused a short circuit between pin 3 (signal wire) and pin 1 (ground). Dried the connector with compressed air, applied electronic contact cleaner, and replaced the seal ring. The fault cleared. Check the left rear quarter panel vent seal strip for deterioration.
BYD DTC AI Analysis

Wiring harness crimping after accident repair caused short circuit on Qin 100

✓
The vehicle was rear-ended on the left side. After the left rear quarter panel was replaced at an external repair shop, DTC B16E0-00 set. Inspection revealed that when reinstalling the interior trim panel, the technician had routed the left rear impact sensor harness (yellow corrugated tubing) beneath the seat mounting bolt. The bolt washer crushed the insulation, allowing the copper wires to contact the chassis directly. Re-routed the harness, secured it with dedicated clips, and replaced the damaged wire section. Fault cleared.
BYD DTC AI Analysis

Qin EV450 sensor internal short circuit

✓
The airbag warning light illuminated intermittently during normal use, with increased frequency in humid weather. A wiring harness check found no short to earth, but measuring the left rear impact sensor alone showed a resistance of only 12 Ω (normal is several kilohms). This pointed to an internal MEMS accelerometer circuit fault causing a power short to earth. Replaced the left rear impact sensor (part number 5A-3638400), performed configuration coding and adaptation, and fully resolved the fault.
BYD DTC AI Analysis

Retrofitting a reversing camera damaged the wiring harness.

✓
The owner installed a surround-view camera system themselves. While drilling to route wiring on the left rear side, the drill bit damaged the factory left rear impact sensor harness, breaching the insulation and exposing the copper core. The exposed core contacted the body metal, triggering DTC B16E0-00. Removed the left rear quarter trim panel and found a ~3mm wound in the harness from the drill. Cut out the damaged section, spliced in a heat-resistant wire (0.5mm², 125°C rated) by soldering, and sealed with double-layer heat shrink tubing. Normal operation restored.
Other Atto 3 Fault Codes
P0A0DBattery Energy Control Module Requested MIL IlluminationP0AA6Hybrid Battery Voltage System Isolation FaultP1A00Drive Motor "A" Performance — BYD proprietaryB1108For 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.
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.