AU
C050600

DTC C050600 indicates the IPB (Intelligent Integrated Braking System) detects an electrical circuit fault in the right front wheel speed sensor (WSS) — Qin Plus

Braking System

DTC C050600 indicates the IPB (Intelligent Integrated Braking System) detects an electrical circuit fault in the right front wheel speed sensor (WSS).

This is a circuit integrity fault.

The ECU detects sensor signal voltage outside the normal threshold (typically 0.1V-4.9V), a short to power or ground, an open circuit, or signal interference.

The BYD IPB system uses a two-wire Hall effect or magnetoelectric wheel speed sensor.

The ECU continuously monitors the sensor supply current and signal waveform.

If the right front wheel speed signal is lost or distorted, the system disables functions relying on wheel speed data, including ABS, EBD, TCS, ESC, and AEB.

The vehicle retains basic hydraulic braking capability.

This fault illuminates multiple instrument cluster warning lights (ABS/ESC/AEB) and triggers Limp Home mode, which limits power output or disables energy recovery.

5
Cases Logged
5
Causes
Likely Causes — Qin Plus
  • 1Physical damage to the right front wheel speed sensor wiring harness: Routed near the steering knuckle, the wiring harness bends repeatedly during suspension travel and steering. This causes fatigue fractures in the internal copper wires or insulation damage, especially after driving over rough roads or wading.
  • 2Sensor connector corrosion or poor contact: Mud and water accumulate in the right front wheel area. The sensor connector seal (typically located near the shock absorber or fender liner) degrades and fails, causing pin oxidation, short circuits from water ingress, or increased contact resistance (>1Ω).
  • 3Wheel speed sensor internal fault: Damaged internal Hall element, open or shorted coil (magnetic induction type resistance must be 1.0-2.0kΩ; values outside this range indicate failure), or abnormal gap between the sensor head and tone ring due to impact damage (standard gap: 0.3-1.2mm).
  • 4IPB control unit internal sampling circuit fault: Damage to the ECU internal signal processing chip, sampling resistor, or filter capacitor causes incorrect detection of the right front wheel speed channel. Intermittent false readings on other wheel speed channels typically accompany this fault.
  • 5Electromagnetic interference or abnormal reference voltage: Installing aftermarket electronic equipment (such as high-power radios or xenon headlights) causes 12V power supply fluctuations, or excessive voltage drop in the IPB power supply/ground circuit affects sensor 5V reference voltage stability.
What To Do
  • 1
    Initial diagnosis: Use VDS2000/3000 or Launch X-431 to read all fault codes. Check for related faults such as C050500 (left front) and C050700 (right rear). Record freeze frame data parameters such as vehicle speed, voltage, and temperature.
  • 2
    Visual inspection: Raise the vehicle, remove the right front wheel and fender liner, and inspect the complete routing of the wheel speed sensor wiring harness from the IPB control unit (located on the engine compartment firewall or above the cabin pedals) to the right front steering knuckle. Check the wiring harness at the suspension control arm retaining clips and the steering knuckle bend for wear, insulation damage, or crush marks.
  • 3
    Connector inspection: Disconnect the right front wheel speed sensor connector (2-pin) and the corresponding IPB connector. Measure the resistance between the pins (normal: 0.5-2Ω). Measure the insulation resistance to ground (should be >10MΩ). Check the connector for verdigris, water stains, or backed-out pins.
  • 4
    Sensor body inspection: Remove the right front wheel speed sensor, clean metal filings from the sensor head, measure the sensor resistance (magnetic induction type: 1.0-2.0kΩ; Hall type: apply power to measure signal voltage), and check the tone ring for missing teeth, deformation, or oil contamination.
  • 5
    Dynamic monitoring: Connect the diagnostic tool and perform a road test. Monitor the four-wheel speed live data stream. Check the right front wheel speed signal for jumps, lag, or excessive deviation from the other wheels (during normal driving, the difference between all four wheels should be <2km/h).
  • 6
    Repair and replacement: If the wiring harness is damaged, repair using waterproof heat-shrink tubing or replace the wiring harness assembly; if the sensor fails, replace with an OEM wheel speed sensor (verify the part number against vehicle configuration; Song PLUS DMi typically uses the 36xxxxx series); if the IPB is faulty, update the software or replace the IPB assembly (requires bleeding and calibration).
  • 7
    Verification and calibration: Clear the fault code, bleed the IPB system (if servicing the hydraulic system), perform wheel speed sensor signal learning (use a diagnostic tool to perform tone ring deviation learning on applicable models), and road test the vehicle for 5-10km to confirm the fault does not recur and ABS/ESC functions operate normally.
Real-World Cases
BYD DTC AI Analysis

Song PLUS DMi Right Front Wheel Speed Sensor Harness Wear from Suspension Contact

✓
Mileage 28,000km. ABS warning light came on intermittently when driving on rough roads. VDS read history code C050600. Inspection found the right front wheel speed sensor harness interfering between the steering knuckle and lower control arm bracket. The outer insulation had worn through exposing the shielding, with 3 internal copper wires broken. Repaired the harness by soldering and sealing with waterproof heat-shrink tubing, repositioned the harness clips, and added corrugated tube protection. Fault resolved.
BYD DTC AI Analysis

Right front wheel speed sensor short circuit after driving through water

✓
After driving through standing water during heavy rain, the dashboard displayed a brake system fault. Diagnosis revealed active DTC C050600. The right front wheel speed sensor connector measured 0.8 Ω to ground (shorted). Removing the sensor revealed internal water ingress and a burnt-out Hall element. Replaced the sensor, dried the connector and applied dielectric grease. Fault resolved.
BYD DTC AI Analysis

Intermittent fault caused by IPB software false positive

✓
No driveability issues, but DTC C050600 set frequently and returned within 50 km after clearing. Checked wiring harness and sensor — both normal. Sensor signal waveform showed high-frequency noise. Per TSB, this batch of IPB control units with software V1.02 has a sampling circuit filtering algorithm defect. Fix: Updated IPB software to V1.05, performed control unit coding and longitudinal acceleration sensor calibration. Fault has not returned.
BYD DTC AI Analysis

Non-OEM tires causing false wheel speed signal discrepancy detection

✓
Owner fitted a non-OEM-spec tyre to the right front (diameter difference >3%). This caused the right front wheel speed to consistently differ from the other three wheels by more than 5 km/h. The IPB flagged the right front wheel speed sensor signal as implausible and stored DTC C050600. This was not a wiring harness fault, but the fault code definition covers signal plausibility checks. Fix: Replaced the tyre with an OEM-spec unit, performed tyre pressure matching and wheel speed synchronisation learning. System returned to normal.
BYD DTC AI Analysis

Right front wheel speed sensor connector pin backed out, poor contact

✓
After accident repairs (right front wing panel), the ABS light stayed on. Inspection found the right front wheel speed sensor connector had been disconnected and reconnected during the crash repair, but the female terminals on the IPB side were not fully inserted and locked. Driving vibrations caused an intermittent open circuit, with resistance fluctuating between 0.3–50Ω. Repair: Used a dedicated pin removal tool to resecure the terminals, ensuring the locking tabs engaged properly. Measured continuity resistance below 0.5Ω. Fault cleared.
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.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.