AU
C058200

DTC C058200 indicates the supply voltage to the brake booster motor inside the IPB (Intelligent Integrated Braking System / One-box electro-hydraulic brake-by-wire system) falls outside the normal operating threshold set by the ECU (typically 9-16V DC) — Seal 6 EV

Braking System

DTC C058200 indicates the supply voltage to the brake booster motor inside the IPB (Intelligent Integrated Braking System / One-box electro-hydraulic brake-by-wire system) falls outside the normal operating threshold set by the ECU (typically 9-16V DC).

This brushless DC motor drives the brake master cylinder to generate hydraulic brake assist.

A generator regulator fault, a power supply circuit short, or reversed polarity during jump-starting can cause high voltage (>16V).

A discharged battery, excessive wiring voltage drop, poor ground connection, or internal module DC-DC power supply chip failure can cause low voltage (<9V).

This fault triggers the IPB degraded mode, reducing or completely disabling the brake assist function (hard brake pedal).

The fault may also inhibit ABS/ESC/EBD functions.

In severe cases, the system illuminates the red brake warning lamp, compromising driving safety.

5
Cases Logged
5
Causes
Likely Causes — Seal 6 EV
  • 1Fault in the IPB electro-hydraulic module internal DC-DC converter, MOSFET drive circuit, or voltage sampling resistor, causing abnormal motor power supply.
  • 2Battery aging, low charge (voltage <11V), or alternator regulator fault causing excessive output voltage (>15.5V)
  • 3Poor contact, loose connections, backed-out terminals, or burnt terminals in the IPB power supply circuit or fuses (such as F1/16, F2/03, or F4/15, depending on vehicle configuration)
  • 4Vehicle modifications (such as installing high-power electrical accessories or wiring a dashcam to constant power) causing power supply interference or sudden load changes.
  • 5The connections between the front compartment wiring harness and body ground points (G101/G102) are loose or oxidized, increasing circuit resistance and causing a voltage drop.
What To Do
  • 1
    Use the VDS2000 or a dedicated BYD diagnostic tool to read the complete fault codes and freeze frame data. Record the specific voltage, vehicle speed, brake pedal travel, and IPB temperature at the time of the fault to determine whether the fault is continuous or intermittent.
  • 2
    Measure the battery static voltage (normal 12.4-12.8V) and dynamic voltage (idle 13.8-14.4V, acceleration <15.0V). Check the generator output waveform to rule out a charging system fault.
  • 3
    Check the IPB module fuses and connectors (usually located in the front compartment left/right power distribution box, and IPB module body connectors CN1/CN2). Inspect the pins for backing out, corrosion, or water ingress. Measure the voltage drop between the power supply pins (constant power +B, ignition IG1) and ground (GND). The voltage drop must be <0.1V.
  • 4
    Perform the IPB system function test: execute the bleeding procedure, pedal feel simulation test, and hydraulic circuit test in sequence. Observe the motor operating current (normal <15A) and voltage fluctuations.
  • 5
    If the wiring and power supply are normal and the fault persists, replace the IPB electro-hydraulic control unit assembly (part number varies by vehicle model; e.g., Song PLUS DM-i: 6A-3555100-70). After replacement, perform coding configuration, longitudinal sensor calibration, and the ESC bleeding procedure.
Real-World Cases
BYD DTC AI Analysis

Burnt fuse holder on Song PLUS DM-i causing voltage drop

✓
Vehicle presented with intermittent ABS/ESC warning lights and stiff brake pedal while driving. DTCs C058200 (current) and U012187 (history) read. IPB supply voltage measured 8.2 V during fault reproduction; battery voltage remained normal. Front compartment fuse box inspection revealed the IPB 30A fuse (F2/03) holder burnt and pins loose, increasing contact resistance under high current. Replaced the fuse box holder and fuse, polished the IPB connector pins, and retightened the ground cable. Fault resolved.
BYD DTC AI Analysis

Qin PLUS DM-i: Sudden voltage drop during cold start

✓
Owner reported dashboard warnings during cold starts in northern winter. DTCs C058200 and C003F00 (brake booster motor fault) stored. Measurements checked normal at ambient temperature, but during a -15°C cold start, battery voltage dropped instantly to 9.5V. The IPB internal power supply chip failed to maintain stable output due to poor low-temperature characteristics. Replaced the IPB electro-hydraulic module assembly and recommended the owner install an AGM battery with better low-temperature performance. The fault has not reoccurred.
BYD DTC AI Analysis

Aftermarket dashcam causing power interference on Dolphin

✓
The owner fitted a dashcam themselves, splicing into the IPB fuse for constant power, causing intermittent C058200 faults while driving. Inspection found the modified wiring had damaged insulation and shorted to the body, creating voltage fluctuations in the IPB supply. Factory wiring was restored, with a separate feed run from the battery positive via the fuse box, returning the IPB system to normal. Do not tap into brake system fuses for modifications.
BYD DTC AI Analysis

Han EV IPB internal MOSFET failure

✓
While driving, the red brake system warning light suddenly illuminated and the pedal went hard with almost no boost. Scanned DTC C058200 (voltage too high, freeze frame showed 16.8V). Checked alternator and battery voltage – normal. Measured power input at the IPB connector – normal, but the module internally detected an abnormal motor supply. Disassembled the IPB and found the internal motor drive MOSFET had shorted, causing the detection circuit to report voltage out of range. Replaced the IPB assembly and recalibrated. Issue resolved.
BYD DTC AI Analysis

Tang DM-p poor ground connection causing intermittent fault

✓
ABS warning light came on intermittently when driving on rough roads. Read DTC C058200 (low voltage). Found the G101 ground point bolt in the left front engine bay loose and oxidized. The IPB draws high current (20A peak); poor grounding caused circuit voltage drop, and the module detected voltage below threshold. Cleaned the ground point, tightened the bolt to specified torque (10N·m), and applied conductive paste. Fault resolved.
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: Official This information is for reference only. Always consult a qualified technician for diagnosis and repair. Do not attempt high-voltage system repairs yourself.