C0142 is a manufacturer-specific chassis/ABS diagnostic trouble code. Its exact definition can vary depending on the vehicle manufacturer, ABS system, model year, and application. On applicable vehicles, the code is associated with a fault involving the ABS hydraulic pressure sensor circuit.
The fault may involve the hydraulic pressure sensor, sensor wiring, electrical connector, power or reference circuit, ground circuit, hydraulic control unit, or ABS control module. The exact component and diagnostic procedure should always be confirmed using vehicle-specific service information.
Fault Code Description
C0142 refers to an ABS/chassis-related fault involving the hydraulic brake-pressure sensing circuit on applicable vehicle applications.
Code type: Manufacturer-Specific Chassis / ABS Diagnostic Trouble Code.
Likely fault area: Hydraulic pressure sensor, sensor connector, wiring, power or reference circuit, ground, hydraulic control unit, or ABS control module.
Important: C0142 is not a universal generic OBD-II definition. Different manufacturers may use the same C-code differently. Therefore, the vehicle make, model, year, and ABS system should be identified before applying a specific diagnostic procedure.
What Does C0142 Mean?
The ABS system monitors hydraulic brake pressure as part of its electronic braking-control strategy. The control module uses pressure information when managing functions such as ABS braking and, on applicable vehicles, traction and stability control.
When the pressure-sensor signal or its electrical circuit does not behave as expected, the ABS control system may store C0142.
A stored C0142 does not automatically mean that the pressure sensor has failed. Electrical problems such as an open wire, short circuit, high resistance, poor connector contact, incorrect reference voltage, or poor ground can also cause the code.
Symptoms of C0142
- ABS warning light.
- Traction-control warning light.
- Stability-control warning indicator.
- Brake-system warning message on applicable vehicles.
- ABS function may be disabled.
- Traction-control or stability-control functions may be unavailable.
- Abnormal hydraulic-pressure readings on a scan tool.
- Additional ABS or chassis fault codes.
- Normal basic braking may remain available in some cases.
Common Causes of C0142
- Faulty hydraulic brake-pressure sensor.
- Open pressure-sensor circuit.
- Short circuit in the sensor wiring.
- High resistance in the circuit.
- Damaged electrical connector.
- Corroded or loose connector terminals.
- Incorrect sensor power or reference voltage.
- Poor sensor ground.
- Damaged wiring near the ABS hydraulic unit.
- Moisture or water intrusion.
- Hydraulic control-unit fault.
- ABS control-module fault.
C0142 Manufacturer Example
Because C0142 is manufacturer-specific, the exact definition should not be assumed to be identical across all vehicles. A manufacturer example can help explain how the code may be diagnosed, but the exact service information for the vehicle being repaired should always take priority.
Chevrolet Example
On applicable Chevrolet vehicles, C0142 may be associated with the ABS hydraulic-pressure sensing circuit. Diagnosis should include the pressure sensor, connector, wiring, electrical supply, ground, and ABS control system using the correct Chevrolet service information.
Other Vehicle Applications
Other manufacturers may use C0142 with a different definition or monitoring strategy. Always verify the exact code description against the vehicle manufacturer's diagnostic information before replacing components.
How to Diagnose C0142
1. Scan the ABS System
Use an ABS-capable diagnostic scanner rather than relying only on a basic engine OBD-II scanner. Record C0142 and any additional ABS, traction-control, or stability-control codes.
Additional codes can help determine whether the problem is isolated to the pressure-sensor circuit or is part of a larger ABS-system problem.
2. Check the Brake System
Inspect the brake-fluid level and look for visible hydraulic leaks or other obvious brake-system problems.
If the brake pedal feels unusually soft, hard, or inconsistent, the vehicle should be inspected before continuing normal driving.
3. Inspect the Pressure Sensor Connector
Inspect the pressure-sensor connector for corrosion, moisture, loose terminals, damaged pins, poor terminal tension, or a damaged locking mechanism.
4. Inspect the Wiring
Use the correct vehicle-specific wiring diagram to inspect the complete pressure-sensor circuit.
Look for broken wires, damaged insulation, short circuits, high resistance, wiring pulled tight, or wiring damaged by heat, vibration, or previous repairs.
5. Test Power, Reference and Ground
Check the sensor's power or reference circuit and ground according to the manufacturer's specifications.
Do not assume that all vehicles use the same sensor voltage, pinout, or circuit configuration. The correct wiring diagram should be used for the exact vehicle.
6. Check Pressure Sensor Live Data
Use an ABS-capable scan tool to monitor available hydraulic-pressure data.
When the brake pedal is released, the pressure reading should correspond to the expected resting condition. When the brake pedal is applied, the reading should respond appropriately.
A fixed, implausible, or unstable pressure value may indicate a sensor or circuit problem, but live data should always be compared with the manufacturer's specifications.
7. Test the ABS Control System
If the pressure sensor, wiring, connector, power, reference, and ground circuits are confirmed to be correct, follow the manufacturer-specific procedure for testing the ABS hydraulic control unit and ABS control module.
The ABS module should not be replaced simply because C0142 is stored.
C0142 Diagnostic Signal Flow
↓
Master Cylinder / Hydraulic Pressure
↓
Hydraulic Pressure Sensor
↓
Sensor Signal Circuit
↓
ABS Control Module
↓
ABS / Traction / Stability Control
C0142 OBD Live Data
Depending on the vehicle, an ABS-capable scan tool may provide hydraulic brake-pressure data, brake-pedal status, wheel-speed information, ABS status, traction-control status, and stability-control parameters.
Monitor the pressure value while slowly applying and releasing the brake pedal. The signal should change in a logical manner according to the vehicle manufacturer's specifications.
Live data is especially useful when diagnosing an intermittent problem, but it should be combined with electrical circuit testing because a wiring or connector fault may disappear during a stationary inspection.
Is C0142 Serious?
C0142 can be serious because it is associated with the ABS and electronic brake-control system.
Depending on the vehicle, ABS, traction-control, or stability-control functions may be disabled while the fault is active. Basic hydraulic braking may still operate, but the vehicle may not provide the same level of electronic braking assistance or stability control.
If braking performance changes, the brake pedal feels abnormal, or there is a brake-fluid leak, the vehicle should be inspected immediately.
Can I Drive With C0142?
Limited driving may be possible when normal braking remains unaffected, but C0142 should be diagnosed as soon as possible.
Avoid unnecessary driving if the ABS warning is accompanied by reduced braking performance, an abnormal brake pedal, a hydraulic leak, or multiple brake-system warning indicators.
C0142 Repair Cost
- ABS diagnostic scan: approximately $50–$150+.
- Electrical diagnosis: approximately $80–$200+.
- Wiring repair: approximately $80–$300+.
- Connector repair: approximately $80–$200+.
- Pressure sensor replacement: approximately $150–$500+ where separately serviceable.
- ABS hydraulic control unit: approximately $500–$1,500+.
- ABS control module replacement or programming: approximately $500–$1,500+ depending on the vehicle.
These are general estimates only. Actual repair costs depend on the vehicle manufacturer, model, ABS design, parts availability, programming requirements, and local labor rates.
Common Repair Mistakes
- Replacing the pressure sensor without testing the circuit.
- Replacing the ABS module immediately after seeing C0142.
- Ignoring connector corrosion.
- Failing to test sensor power and ground.
- Using an engine-only OBD-II scanner.
- Ignoring additional ABS codes.
- Using the wrong wiring diagram.
- Assuming C0142 has the same definition on every vehicle.
- Skipping live-data analysis.
- Failing to check for hydraulic brake problems.
Related OBD2 Codes
- C0139 – Brake-pressure sensor/circuit-related fault on applicable systems.
- C0140 – Brake-pressure sensor/circuit-related fault on applicable systems.
- C0141 – ABS hydraulic-pressure sensor circuit-related fault on applicable applications.
- C0142 – ABS hydraulic-pressure sensor circuit-related fault on applicable applications.
- C0040 – Wheel-speed sensor circuit-related fault on applicable vehicles.
- C0045 – Wheel-speed sensor circuit-related fault on applicable vehicles.
Related C-codes are also manufacturer-dependent. Their exact definitions should be verified using the diagnostic information for the vehicle being repaired.
FAQ About C0142
What does C0142 mean?
C0142 is a manufacturer-specific chassis/ABS diagnostic code. On applicable systems, it is associated with a fault involving the ABS hydraulic pressure sensor circuit.
Is C0142 a generic OBD-II code?
No. C0142 is a manufacturer-specific chassis/ABS code. Its exact definition can vary between manufacturers, ABS systems, and model years.
Can a bad pressure sensor cause C0142?
Yes. A defective hydraulic pressure sensor can cause C0142, but the sensor should not be replaced until its connector, wiring, power, reference, and ground circuits have been tested.
Can wiring cause C0142?
Yes. An open circuit, short circuit, high resistance, damaged wiring, or poor connector contact can interfere with the pressure-sensor signal and trigger C0142.
Can C0142 turn on the ABS light?
Yes. Because C0142 is associated with the ABS system, the ABS warning light and, depending on the vehicle, traction or stability-control warning indicators may illuminate.
Does C0142 mean the ABS module is bad?
No. The ABS module is only one possible cause. The pressure sensor, wiring, connector, power, reference, and ground circuits should be tested before considering module replacement.
How do I fix C0142?
Start by scanning the ABS system, checking related codes, inspecting the pressure sensor and connector, testing the wiring and electrical circuits, and verifying pressure-sensor live data. Replace the failed component only after the actual fault has been confirmed.
What is C0142 on Chevrolet?
On applicable Chevrolet vehicles, C0142 may be associated with an ABS hydraulic-pressure sensing circuit. However, the exact Chevrolet definition, circuit design, and diagnostic procedure should be confirmed for the specific model and model year.
Final Takeaway
C0142 is a manufacturer-specific chassis/ABS diagnostic trouble code. On applicable vehicles, it can indicate a problem involving the ABS hydraulic pressure sensor circuit.
The possible causes include the pressure sensor, wiring, connector, power or reference circuit, ground, hydraulic control unit, or ABS control module. Because the meaning and circuit configuration can vary between manufacturers, the exact vehicle application should always be confirmed before replacing any component.
Chevrolet is one example of a vehicle manufacturer where C0142 may be encountered, but the diagnostic principles should not be automatically applied to every vehicle using the same code.