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C059592

The IPB (Intelligent Power Brake) system triggers this DTC when the internal power drive circuit of the Electrical Booster detects an abnormal power supply — Seal 6 EV

Braking System

The IPB (Intelligent Power Brake) system triggers this DTC when the internal power drive circuit of the Electrical Booster detects an abnormal power supply.

The IPB system integrates the conventional vacuum booster, ABS, ESP, and EPB into a single unit, and uses a motor-driven hydraulic system to generate brake assist.

DTC C059592 indicates the control module detects the booster motor supply voltage falls outside the normal threshold (typically 9-16V), or the internal DC-DC conversion circuit, power drive MOSFET, or power management chip operates abnormally.

This fault disables or limits the electric brake assist function and significantly stiffens the brake pedal (requiring over 200N of pedal force).

Simultaneously, the system triggers safety protection mechanisms, restricting ADAS functions such as Autonomous Emergency Braking (AEB) and Adaptive Cruise Control (ACC), severely compromising driving safety.

5
Cases Logged
Real-World Cases
BYD DTC AI Analysis

Loose power supply connection caused power assist failure in Seal 06 DM-i

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Dashboard showed brake system fault, ESP warning light illuminated, and brake pedal became hard. Scan tool read IPB system DTC C059592 (Electrical booster power supply abnormal). Found loose connection in IPB power supply fuse holder; voltage dropped to 8.2V under high current. Repaired fuse holder terminals and tightened power wiring harness connectors to clear the fault. One week later the fault returned. Further testing found intermittent open circuit in IPB internal power module. Replaced IPB assembly and performed calibration to resolve.
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BYD DTC AI Analysis

Excessive battery voltage drop during cold start triggered Han EV fault

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The owner reported occasional heavy brake pedal on cold starts, with the instrument cluster displaying "Check Brake System". The fault cleared after warmup. Retrieved historical DTC C059592. Testing revealed battery degradation (internal resistance 18mΩ, state of health 62%). Voltage dropped to 8.5V at startup, causing insufficient power to the IPB assist motor and triggering protection. Replaced the battery and tightened the IPB ground lead. Monitored cold starts for one week with no recurrence.
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BYD DTC AI Analysis

Song PLUS DM-i IPB poor heat dissipation causing intermittent fault

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While driving, the instrument cluster suddenly displayed a brake system fault. The ABS and ESP warning lights illuminated and brake pedal travel increased. Scanning revealed codes C059592 and C058200 (abnormal motor circuit signal). The fault occurred intermittently, returning after 50-100 km once cleared. Inspection showed the IPB mounted close to the turbocharger; a missing heat shield caused internal overheating of the control unit, activating thermal protection in the power module. Reinstalled the heat shield, cleaned the IPB connector and applied conductive grease. The fault has not recurred.
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BYD DTC AI Analysis

Qin PLUS DM-i brake booster motor internal short circuit

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The brake pedal gradually hardened until almost no assist remained, with the instrument panel showing continuous warnings. Retrieved DTC C059592. Measured IPB supply voltage at 12.8V (normal), but the scan tool showed abnormal booster motor current: peak exceeded 30A then suddenly dropped to zero. Disassembled the IPB and found partial short circuit in the brake booster motor windings, triggering internal drive circuit overload protection. Replaced the IPB integrated brake unit assembly, calibrated the yaw rate sensor, bled the brakes, and cleared the fault.
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BYD DTC AI Analysis

Water ingress corroded the Dolphin's IPB connector, causing abnormal power supply.

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Brake system fault after vehicle drove through water; dashboard displayed "Service Brake System". Found IPB connector seal damaged with water inside and green corrosion on pins. Cleaned and dried connector; fault temporarily cleared but returned after two days. Measured power pin contact resistance at 3.2Ω (normal <0.5Ω), causing voltage drop to booster motor under load. Replaced IPB wiring harness connector, cleaned ground point, and replaced IPB assembly (internal circuit corrosion). Fault fully resolved.
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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.