This fault code indicates the IPB (Integrated Power Brake) system detects pressure inside the brake booster chamber below the normal operating threshold — Atto 8
This fault code indicates the IPB (Integrated Power Brake) system detects pressure inside the brake booster chamber below the normal operating threshold.
In models such as the Song PLUS DM-i, the IPB system generates brake assist pressure via an electric vacuum pump or direct motor drive and continuously monitors this pressure using a pressure sensor.
The system triggers DTC C002192 when it detects assist pressure remaining below the target value (typically below -0.6bar or the set threshold range) for longer than the specified time (e.g., 500ms) and rules out sensor signal interference.
This fault causes a hard brake pedal and increased braking distance.
The system restricts the regenerative braking function and illuminates the ABS/ESC warning light.
Extreme conditions may trigger Limp Home mode, severely compromising driving safety.
- 1Electric vacuum pump assembly fault: Worn vacuum pump motor carbon brushes, aging pump body vanes, or a drive circuit fault prevents the pump from building sufficient vacuum (common in vehicles with over 60,000 km).
- 2IPB integrated module internal pressure sensor fault: Sensor signal drift, internal circuit fault, or seal failure between the sensor and the hydraulic chamber, causing a false low-pressure reading.
- 3Vacuum line system leak: Aged or cracked vacuum lines, failed vacuum reservoir sealing ring, loose line joints, or a sticking check valve causing insufficient vacuum retention.
- 4IPB module internal hydraulic circuit fault: Stuck boost solenoid valve, damaged internal sealing ring, or hydraulic fluid leak prevents boost pressure buildup.
- 5Abnormal power supply: Burnt IPB module main relay contacts, excessive fuse contact resistance, or a loose ground circuit causes insufficient supply voltage to the assist motor/vacuum pump.
- 1Use the VDS2000/VDS3000 diagnostic tool to read the DTC freeze frame data. Record the vehicle speed, brake pedal travel, Brake Booster Pressure, and vacuum pump status at the time of the fault to determine whether the fault is intermittent or persistent.
- 2Visually inspect the IPB module exterior for signs of brake fluid leakage. Check the wiring harness connectors (especially the 24-pin main connector) for oxidation or looseness. Check the vacuum lines (if applicable) for cracks, collapse, or loose connections.
- 3Access the IPB system data stream and read the 'Brake Booster Pressure' real-time value. With the ignition ON (brake pedal released), the normal value is -0.8 to -1.0 bar (vacuum). A reading near 0 bar or atmospheric pressure indicates the system failed to build vacuum or the sensor failed.
- 4Perform the vacuum pump actuation test: Activate the electric vacuum pump using the diagnostic tool. Listen for normal pump operation sounds (no abnormal noise, stable speed) and observe the pressure drop rate. Normally, pressure drops from 0 to below -0.7 bar within 3 seconds. If pressure drops slowly or the vacuum pump does not operate, check the vacuum pump power supply (12V) and ground circuit.
- 5Perform a vacuum hold test: Run the vacuum pump until the system reaches maximum vacuum, then stop the pump and observe the pressure drop for 1 minute. If the pressure drop exceeds 0.1 bar/min, a vacuum leak exists. Inspect the sealing of the vacuum reservoir, one-way valve, vacuum booster body, and lines section by section.
- 6Check IPB module power supply and communication: Measure the voltage at the IPB module power terminals (+30, +15) (should be ≥12.4V). Check the CAN-H and CAN-L line voltages (approx. 2.5V) and terminating resistance (approx. 60Ω) to rule out sensor false alarms caused by low voltage.
- 7If the vacuum system is normal but pressure sensor data is abnormal, or the IPB internal hydraulic unit leaks, replace the IPB integrated electro-hydraulic brake module assembly (part number usually starts with 6A). After replacement, use a diagnostic tool to perform the 'IPB Bleeding Procedure' and 'Pressure Sensor Zero Point Calibration'.
- 8Clear the fault code and perform a road test to verify: on a flat, straight road, perform multiple medium- to high-speed braking applications (40km/h→0). Confirm the brake pedal effort is normal, the ABS/ESC warning light is off, and the fault code does not recur.
Song PLUS DM-i: Worn vacuum pump carbon brushes cause intermittent DTCs
IPB module pressure sensor drift false alarm
Stuck vacuum line check valve causing pressure leak
Outdated IPB module software caused false fault codes.