AU
C053B00

DTC C053B00 indicates an open circuit or abnormal voltage in the ABS solenoid valve power supply circuit inside the IPB (Intelligent Integrated Braking) module — Seal U

Braking System

DTC C053B00 indicates an open circuit or abnormal voltage in the ABS solenoid valve power supply circuit inside the IPB (Intelligent Integrated Braking) module.

This fault means the ECU detects the power supply line voltage to the ABS hydraulic modulator solenoid valve falls outside the normal range (typically below 9V or above 16V) or has an open circuit.

Because the IPB system integrates ABS, ESP, EHB (Electro-Hydraulic Braking), and other functions, an abnormal solenoid valve power supply causes safety functions such as anti-lock braking and vehicle stability control to fail or degrade.

The system then enters fail-safe mode.

External power supply circuit issues (fuses, wiring harnesses, connectors) or a fault in the IPB internal power management circuit can cause this fault.

Repair the system immediately to ensure braking system reliability.

5
Cases Logged
5
Causes
Likely Causes — Seal U
  • 1IPB/ABS system fuse in the front compartment power distribution box (usually 30A or 40A) is blown, loose, or making poor contact, causing power supply interruption or excessive voltage drop.
  • 2IPB module power wiring harness connector (located in the front compartment near the firewall): terminal oxidation, terminal back-out, ablation, or water ingress due to poor sealing, resulting in increased contact resistance.
  • 3Poor contact, open circuit, or short circuit due to damaged insulation in the main power harness from the battery to the IPB module, especially harness aging in the high-temperature engine compartment.
  • 4Internal power supply circuit fault in the IPB hydraulic modulator assembly, such as a damaged DC-DC converter module, filter capacitor, or solenoid valve driver chip.
  • 5IPB module ground circuit (usually the body ground point) is loose, oxidized, or corroded, causing increased circuit resistance and reference voltage drift.
What To Do
  • 1
    Use the VDS2000/VDS1000 diagnostic tool to read all fault codes. Check if C053C00 (wheel speed sensor) or other communication fault codes accompany C053B00, and record the freeze frame data.
  • 2
    Check the status of the ABS, ESP, and brake system warning lights on the instrument panel. Perform a brake pedal feel test to confirm whether the IPB system has entered backup mode (pedal becomes hard).
  • 3
    Measure the battery static voltage (≥12.4 V) and the voltage after startup (13.5–14.5 V) to rule out a vehicle power supply system fault.
  • 4
    Check if the IPB-related fuses in the front compartment power distribution box, such as F1/17 and F1/18 (30A/40A), have blown. Measure the voltage drop across the fuse holder with a multimeter, and inspect the base for burn marks or blackening.
  • 5
    Disconnect the IPB module wiring harness connector (release pressure first to prevent brake fluid leakage). Inspect power supply pins, including pin 1 (constant power +30) and pin 32 (IGN power +15), for oxidation, backed-out pins, or burning. Measure the supply voltage; it must be 12V±0.5V.
  • 6
    Check the IPB module ground wire connection status (usually ground point G101 or G102). Measure the ground resistance; it must be <1Ω. Clean the ground point and apply conductive grease.
  • 7
    Trace the front compartment wiring harness and inspect the ABS solenoid valve power supply circuit insulation for damage. Focus on the harness protective sleeve near high-temperature engine areas and the firewall pass-through.
  • 8
    If the external circuit tests normal (12V, good ground, circuit continuity), diagnose an internal power supply circuit fault in the IPB hydraulic modulator assembly. Replace the IPB assembly with ECU.
  • 9
    After replacing the IPB, perform the following: brake system bleeding procedure, yaw rate sensor calibration, steering angle sensor calibration, and longitudinal acceleration sensor calibration.
  • 10
    Clear the fault code and perform a road test (including an ABS activation test) to verify the fault code does not return and the brake system functions normally.
Real-World Cases
BYD DTC AI Analysis

Song PLUS DM-i: Poor fuse contact caused ABS valve power supply fault

✓
ABS and ESP warning lights illuminated intermittently while driving, and the brake pedal became stiff. Read DTC C053B00 using VDS2000. Inspected the front compartment fuse box and found the IPB fuse (40A) base burnt and blackened. Poor contact between the fuse and base caused excessive voltage drop (measured at only 8.5V). Replaced the fuse box base and fuse, cleaned the IPB power connector pins, applied conductive grease. Fault resolved.
Original source ↗
BYD DTC AI Analysis

Qin Pro DM multi-system faults with abnormal ABS valve power supply

✓
Dashboard showed multiple warnings: "Check Engine System", "ABS System", and "Network". Braking felt abnormal. Diagnosis revealed communication faults between the ECM, ESP, and other modules, with DTC C053B00. Inspection found the ESP fuse loose in the front compartment fuse box, causing intermittent power interruption to the IPB module. Secured the fuse and checked the ESP module harness connector; found slight oxidation on the IGN power pin. Cleaned the terminal and recalibrated the sensors. Fault cleared.
Original source ↗
BYD DTC AI Analysis

Water ingress and corrosion caused IPB supply voltage fault in Song MAX

✓
Intermittent no-start condition. With the brake pedal depressed and start button pressed, the vehicle fails to start and the dashboard displays a brake system fault. DTC C053B00 stored. Found low supply voltage to the ESP module (10.2V). Traced the wiring harness and found the connector seal between the front compartment harness and IPB valve body had degraded, allowing water ingress and pin corrosion. Cleaned and dried the connector, replaced the corroded pins and seal, and resealed the wiring harness. Fault resolved.
Original source ↗
BYD DTC AI Analysis

Han EV: IPB Internal Power Module Failure and Replacement Case

✓
The dashboard constantly displayed "Brake System Fault" with the ABS and ESC lights on. The scan tool retrieved code C053B00 but could not clear it. The technician measured normal supply voltage at the IPB module (12.3V), confirmed good ground, and verified wiring harness continuity. They diagnosed an internal power management circuit failure in the IPB hydraulic modulator assembly. After replacing the IPB assembly with ECU, they performed brake system bleeding and sensor calibration. The fault code cleared and ABS function returned to normal.
BYD DTC AI Analysis

Tang DM wiring harness wear caused intermittent open circuit in ABS valve power supply

✓
ABS warning light illuminates intermittently on rough roads; normal on flat surfaces. DTC C053B00 (intermittent) stored. Found the power supply harness between the engine bay and IPB chafed at the firewall penetration—prolonged vibration wore through the insulation, causing an intermittent short to ground. Repaired the damaged section, fitted an abrasion-resistant protective sleeve, and re-secured the routing to prevent contact with the body. Fault resolved.
Other Seal U 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.