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C055164

DTC C055164 indicates the IPB (Integrated Power Brake) detects a fault in the Longitudinal Acceleration Sensor signal circuit — Seal 6 EV

Braking System

DTC C055164 indicates the IPB (Integrated Power Brake) detects a fault in the Longitudinal Acceleration Sensor signal circuit.

This sensor monitors longitudinal acceleration (braking deceleration/driving acceleration) and provides key vehicle dynamic parameters to the ESC (Electronic Stability Control), ABS (Anti-lock Braking System), AEB (Autonomous Emergency Braking), and energy recovery systems.

When the fault triggers, the longitudinal acceleration signal status bit the IPB receives via CAN message 0x223 indicates an error (such as invalid signal, checksum error, or timeout), preventing the system from accurately determining the vehicle motion state.

In severe cases, ESC, ABS, and AEB functions may enter a degraded mode or fail completely.

The instrument cluster illuminates multiple brake system warning lamps, and extreme conditions compromise vehicle braking safety and stability control.

4
Cases Logged
Real-World Cases
BYD DTC AI Analysis

Signal Drift in Song Plus DM-i Due to IPB Connector Corrosion After Water Wading

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A 2021 Song PLUS DM-i showed "Brake System Fault" after driving through heavy rain and flood water. Scanner read DTC C055164. The IPB sits on the left side of the engine bay; its wiring harness connector seal had degraded, letting water in that oxidised the longitudinal acceleration signal terminal and created contact resistance (reference voltage dropped from 2.3V to 1.8V). Cleaned the connector, applied conductive paste, and replaced the waterproof seal. Fault resolved.
BYD DTC AI Analysis

Seal 6 DM-i fault after accident repair: calibration not performed

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Following front-end collision repairs that replaced the front bumper and wiring harness, the instrument cluster continuously displayed C055164. Diagnosis revealed the IPB had been replaced but technicians had not performed the sensor zero-point calibration. Ran the 'Longitudinal Acceleration Sensor Calibration' procedure using VDS with the vehicle stationary and level. Cleared the fault code after calibration; ESC function returned to normal.
BYD DTC AI Analysis

Faulty 5V power module inside IPB caused abnormal signals

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A Qin PLUS DM-i with 80,000 km logged DTC C055164. The IPB’s 5V reference supply to the longitudinal acceleration sensor was jumping randomly between 3–5 V. An external stable 5 V supply restored normal sensor signal, isolating the fault to the IPB’s internal power management chip. Replaced the IPB assembly (part number possibly 3568110-XX) and performed online matching. Issue resolved.
BYD DTC AI Analysis

Wiring harness chafing caused intermittent open circuit in the signal circuit

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Vehicle intermittently logs C055164 over speed bumps or rough roads; normal on flat roads. Inspection found the IPB wiring harness chafing against body sheet metal at the firewall penetration. Long-term wear damaged the insulation on the longitudinal acceleration signal wire, causing momentary short to ground over bumps. Repaired the wiring, rerouted and secured the harness, and added anti-abrasion sleeving. Fault has not returned.
Other Seal 6 EV 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: Community This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.