AU
C006208

DTC C006208 indicates the Electronic Stability Program (ESP) control unit detects an abnormal signal from the Longitudinal Acceleration Sensor (LAS) — Qin Plus

Braking System

DTC C006208 indicates the Electronic Stability Program (ESP) control unit detects an abnormal signal from the Longitudinal Acceleration Sensor (LAS).

This sensor, typically integrated within the IPB (Intelligent Integrated Braking System) or ESP hydraulic modulator assembly, monitors the vehicle's longitudinal acceleration (G value) in real time.

It provides a critical input signal for ESP vehicle stability control, TCS traction control, and brake force distribution.

Fault conditions include signal circuit open or short, sensor signal out of range (±1.5g), signal drift, sensor self-test failure, or lost calibration data.

When this fault occurs, the ESP system enters a degraded mode.

Automatic Emergency Braking (AEB), Traction Control (TCS), and Electronic Brakeforce Distribution (EBD) functions may be limited or disabled.

The ESP/ABS warning lights illuminate on the instrument cluster, severely compromising driving stability and braking safety.

The C006208 fault code on the Qin Plus indicates an abnormal signal from the longitudinal acceleration sensor used by the ESP system. Severity is medium, but stability, traction control, EBD, AEB, and warning lights may be affected. Common causes include a faulty sensor inside the IPB module or poor contact, corrosion, or loose pins at the IPB connector. The recommended fix is diagnosis and repair by an authorised dealer. Typical repair cost data is available.
5
Cases Logged
5
Causes
Likely Causes — Qin Plus
  • 1Damaged longitudinal acceleration sensor body or aged chip inside the IPB assembly (sensor typically integrates into the IPB module; not a separate component).
  • 2IPB wiring harness connector (24-pin or 32-pin) loose, backed-out pins, pin corrosion, or poor contact, especially after vehicle wading or underbody scraping.
  • 3Sensor calibration data lost or calibration abnormal (e.g., extended battery disconnection, interrupted IPB software upgrade, or failure to perform sensor calibration after chassis repairs).
  • 4IPB control unit internal power supply circuit fault (damaged 3.3V/5V voltage regulator chip) causing abnormal sensor power supply.
  • 5Front-end collision or severe chassis impact deformed the IPB mounting bracket, physically shifting the internal sensor or damaging the MEMS component.
What To Do
  • 1
    Use BYD VDS or a dedicated diagnostic tool to read complete DTCs, confirm C006208 is a current fault (Active), and record freeze frame data (vehicle speed, raw longitudinal acceleration value, supply voltage, etc.).
  • 2
    Visually inspect the IPB assembly exterior for impact deformation and brake fluid leaks. Inspect the wiring harness connector (located on the side of the IPB assembly) for looseness, backed-out pins, water ingress, and corrosion. Measure the connector latch retention force.
  • 3
    Inspect the vehicle chassis condition. Verify the IPB mounting bracket is not deformed and the fixing bolt torque meets the standard (typically 20±2N·m). Verify the vehicle longitudinal acceleration sensor mounting surface shows no accident deformation.
  • 4
    Measure the IPB supply voltage (B+ terminal should be 12±0.5V; IGN signal normal). Measure the CAN-H and CAN-L voltages (approx. 2.5V) and termination resistance (approx. 60Ω) to rule out wiring faults.
  • 5
    Perform the longitudinal acceleration sensor online calibration: Use the diagnostic tool to enter 'IPB/ESC System' → 'Sensor Calibration' → 'Longitudinal Acceleration Sensor Calibration'. Ensure the vehicle is stationary on a level road surface (gradient <1%), center the steering wheel, and release the brake pedal. Follow the prompts to complete the calibration.
  • 6
    If calibration fails or does not pass, update the IPB software to the latest version, or perform control unit coding configuration (Coding).
  • 7
    Clear the fault code and perform a road test to verify, including 0-60 km/h straight-line acceleration, 40 km/h moderate braking, and low-speed steering conditions. Confirm C006208 does not reappear and ESP function returns to normal.
  • 8
    If the fault persists, replace the IPB assembly (ESP hydraulic modulator with ECU). After replacement, perform longitudinal acceleration sensor calibration, steering wheel angle sensor calibration, and ESC hydraulic system bleeding.
Real-World Cases
BYD DTC AI Analysis

Water ingress corroded the IPB connector, causing intermittent signal faults.

✓
A 2019 BYD E5 exhibited intermittent ESP warning light illumination while driving. Retrieved DTC C006208 (alternating between current and history). Inspection revealed the vehicle had been driven through water. The IPB wiring harness connector (32-pin) showed internal green corrosion. Pin 3 (longitudinal accelerometer signal line) measured 5.2Ω contact resistance (specification <0.5Ω). Cleaned the connector pins, sprayed electronic connector protectant, and reconnected. Fault cleared. Recommend thoroughly checking IPB connector sealing when inspecting water-damaged vehicles.
BYD DTC AI Analysis

Sensors not calibrated after accident repair, causing the DTC to stay on.

✓
An E5 sustained front-end collision damage. After repairs, the ESP warning light remained on, storing DTC C006208. Inspection revealed the IPB assembly had been replaced with a new unit, but the technician did not perform sensor calibration. We executed "Longitudinal Acceleration Sensor Calibration" and "Lateral Acceleration Sensor Calibration" using VDS (C006308 often accompanies this fault), cleared the codes after successful calibration, and road-tested 20 km with no recurrence. Sensor zero-point calibration is mandatory after chassis repairs or IPB replacement.
BYD DTC AI Analysis

IPB internal sensor damaged. Replace complete assembly.

✓
No accident history, yet DTC C006208 persisted and could not be cleared. During sensor calibration, the diagnostic scanner displayed 'longitudinal acceleration raw value: 2.8g' (normal should be approximately 0±0.1g), well outside the reasonable range. Power supply and ground to the IPB tested normal. Wiring harness continuity checked good. Diagnosed the IPB internal longitudinal acceleration sensor (MEMS chip) as faulty. Replaced the IPB assembly and performed calibration and bleed procedures. Fault fully resolved.
BYD DTC AI Analysis

Underbody scrape shifted IPB mounting, causing signal deviation

✓
Underbody scraped a step. Dashboard displayed "Check ESP System". Read DTC C006208. On the hoist, found the IPB mounting bracket deformed and the IPB body rotated approximately 3° relative to the vehicle's longitudinal axis. The longitudinal acceleration sensor is sensitive to mounting angle; this positional shift caused a zero-point error. Straightened the bracket, re-torqued the IPB mounting bolts to 20N·m, performed sensor calibration. Fault cleared.
BYD DTC AI Analysis

Software version bug caused false alarm; fixed with software update

✓
Certain 2018 E5 vehicles intermittently log C006208 on rough roads with no actual hardware fault present. IPB software version V1.02 contains a signal filtering algorithm defect. Upgraded IPB software to V1.05 via VDS (optimised longitudinal acceleration signal sampling filter logic), cleared fault codes, and monitored for one month with no recurrence. For intermittent C006208, check software version first.
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.