C0142 – Meaning, Symptoms, Causes & How to Fix It

C0142 is an ABS/traction control code that usually points to a problem with a wheel speed signal or pressure sensor circuit, depending on the manufacturer. When this code sets, your ABS module has seen something it doesn’t like in the brake control system and is warning you that stability and anti-lock functions may be compromised. You might notice ABS and traction lights on, longer stopping distances on slippery roads, or a change in pedal feel. The car will usually still move, but you should treat this as a safety-related issue and diagnose it soon.

What Does C0142 Mean?

C0142 is a chassis (C) diagnostic trouble code that typically indicates a fault in the ABS or electronic brake control system. On many GM and Toyota vehicles, it’s related to an issue with the brake pressure sensor or a wheel speed/pressure signal that the ABS module uses to manage anti-lock braking and traction control.

In plain language, the ABS/ESC module is seeing an electrical or signal problem from one of its inputs. When that happens, it often disables ABS and stability control and turns on warning lights to let you know the system can’t operate correctly.

Quick Reference

Code: C0142 – ABS/Brake control system fault (pressure or speed signal, depending on make)
Systems affected: ABS, traction control, stability control
Risk level: Moderate to high – braking performance on slippery roads can be reduced
Typical causes: Faulty brake pressure sensor, wiring/connector issues, bad wheel speed input, ABS module fault
Urgency: Diagnose and repair as soon as possible for safe braking

Real-World Example / Field Notes

In the shop, I most often see C0142 on mid-2000s and newer GM SUVs and pickups, and some Toyota and Lexus models. A typical case: customer comes in with ABS and traction lights on, no obvious braking problem in dry weather. Scan tool shows C0142 stored along with a history of intermittent wheel speed or pressure sensor readings. A quick visual inspection finds a cracked sensor connector full of green corrosion from road salt. Clean the connector, repair the terminals, clear the code, and the ABS system comes back to life. In other cases, the brake pressure sensor mounted on the master cylinder is the culprit and needs replacement and calibration.

Symptoms of C0142

ABS warning light on – The amber ABS lamp stays on indicating the system is disabled.
Traction or stability control light on – TRAC, ESC, or VSC lights may illuminate or flash.
Loss of ABS function – Wheels may lock up under hard braking, especially on wet or icy roads.
Longer stopping distances – You may notice the vehicle takes more distance to stop on low-traction surfaces.
Brake pedal feel change – Pedal may feel slightly harder, softer, or “pulsing” differently than normal.
Intermittent warning lights – Lights may come and go with bumps, rain, or temperature changes.
Other ABS codes stored – Codes for specific wheel speed sensors or pressure sensors may appear along with C0142.

Common Causes of C0142

Most Common Causes

Faulty brake pressure sensor – On many vehicles, C0142 points directly to an internal fault or out-of-range signal from the brake pressure sensor mounted on or near the master cylinder.
Damaged wheel speed sensor wiring – Broken, rubbed-through, or corroded wiring harnesses at the front or rear wheel speed sensors can cause intermittent or missing signals that trigger C0142.
Corroded connectors – Moisture and road salt inside ABS module or sensor connectors can create high resistance, causing voltage drop and signal errors.
Failed wheel speed sensor – A sensor that has gone open-circuit or shorted internally can set C0142 along with a more specific speed sensor code.
ABS module internal fault – Less common but possible: internal failure in the ABS/ESC module’s circuitry that misreads a good sensor signal.

Less Common Causes

Low system voltage – Weak battery, poor charging system, or bad grounds can cause the ABS module to see unstable voltage and set false codes.
Aftermarket modifications – Lift kits, larger tires, or incorrect wheel speed ring replacements can throw off the expected sensor signals.
Water intrusion – Flood damage or deep water crossings can fill connectors or the ABS module with moisture and cause internal corrosion.
Mechanical hub or bearing damage – On some designs, the tone ring is integrated into the hub/bearing; damage or excessive play can distort the wheel speed signal.
Incorrect sensor installation – Sensors not fully seated or gapped correctly can create weak or erratic signals.

Diagnosis: Step-by-Step Guide

You’ll want a decent scan tool that can read ABS codes and live data, a digital multimeter (DMM), basic hand tools, and ideally a wiring diagram for your specific vehicle. If you have a more advanced scan tool that can view Mode $06 or manufacturer-specific ABS data, that makes diagnosis easier but isn’t mandatory.

Confirm the code and record data. Connect a scan tool, read all ABS and chassis codes, and note freeze-frame data. See if C0142 is current, pending, or history and whether other wheel speed or pressure sensor codes are present.
Inspect for obvious damage. With the car safely lifted if needed, visually inspect wheel speed sensor wiring at all four corners and the harness to the ABS module and brake pressure sensor. Look for cuts, rubbing, missing clips, or exposed wires.
Check connectors. Unplug the suspected sensor or pressure sensor connectors and look for corrosion, bent pins, water, or loose terminals. Clean and repair as needed, then apply dielectric grease where appropriate.
Monitor live data. Using the scan tool, watch live wheel speed and brake pressure readings while driving slowly in a safe area. All wheel speeds should match closely, and brake pressure should change smoothly when you press the pedal.
Test the suspected sensor electrically. Use a DMM to measure resistance of the wheel speed sensor or brake pressure sensor (if specs are available). Check for open circuits, shorts to ground, or readings far outside the manufacturer’s range.
Verify power and ground. At the sensor connector and ABS module, check for proper reference voltage (often 5V) and solid ground. A missing reference voltage or bad ground can mimic a bad sensor.
Wiggle test the harness. With live data displayed, gently move the harness and connectors near the suspected area. If the signal drops out or spikes when you move it, you’ve likely found an internal break or loose terminal.
Check for TSBs. Look up technical service bulletins for your year/make/model. Some manufacturers have known issues with specific sensors or ABS modules that set C0142 and outline updated parts or reprogramming procedures.
Evaluate the ABS module last. Only after confirming good sensors, wiring, power, and grounds should you suspect the ABS module itself. Many modules can be tested further with bidirectional controls or by comparing signals at the module pins with scan tool data.

Pro tip: When replacing a brake pressure sensor or ABS module on many newer vehicles, you must perform a relearn or calibration procedure with a capable scan tool. Skipping this step can leave C0142 stored even with brand new parts.

Possible Fixes & Repair Costs

Repairs for C0142 range from simple wiring fixes to component replacement and programming. A corroded connector or minor harness repair might cost $50–$200. Replacing a single wheel speed sensor typically runs $150–$350 parts and labor, depending on vehicle and rust level. A brake pressure sensor replacement with calibration can be $250–$500. If the ABS module itself is bad, you may be looking at $600–$1,200 or more. Costs vary with labor rates, part brand (OEM vs aftermarket), and how much rust or disassembly is involved.

Repair or replace damaged wiring/connector to wheel speed or pressure sensor
Replace faulty wheel speed sensor and clear codes
Replace brake pressure sensor and perform calibration/relearn
Clean and reseal corroded ABS module connectors
Replace or remanufacture ABS control module and program it to the vehicle
Address underlying voltage issues (battery, alternator, grounds) if found

Can I Still Drive With C0142?

In most cases, you can still drive with C0142, but you should understand what you’re giving up. When this code sets, the ABS module often disables ABS, traction control, and stability control. Your basic hydraulic brakes still work, but the car will behave like an older vehicle without ABS. That means you can lock the wheels under hard braking and may lose traction more easily in rain, snow, or gravel. Short, careful trips to a shop are usually fine, but avoid high-speed or aggressive driving until it’s repaired.

What Happens If You Ignore C0142?

If you ignore C0142, you’re driving without the safety net of ABS and stability control. On dry pavement you might not notice much difference, but in an emergency stop or on slick roads, you’re at higher risk of skidding, losing steering control, or increasing your stopping distance. Over time, the underlying electrical problem can worsen, potentially leading to additional ABS codes, more expensive repairs, or even intermittent brake assist issues on some systems.

Last updated: March 1, 2026

Key Takeaways

C0142 is an ABS/traction-related chassis code that usually points to a brake pressure or wheel speed signal problem.
The main risk is loss of ABS, traction control, and stability control, especially dangerous on wet or icy roads.
Most causes are sensor or wiring related, not total brake failure, but you should still treat it as a safety concern.
Diagnosis involves checking live ABS data, wiring integrity, sensor resistance, and power/ground at the module.
Repairs can range from a simple connector fix to sensor replacement or, in rare cases, an ABS module replacement.

Vehicles Commonly Affected by C0142

C0142 shows up most often on GM trucks and SUVs (Chevrolet Silverado, Tahoe, Suburban, GMC Sierra, Yukon) and mid-size cars and crossovers from the early 2000s onward. It’s also seen on various Toyota and Lexus models with advanced ABS/ESC systems, including Camry, Corolla, RAV4, Highlander, and ES/RX series. Some Buick, Cadillac, Pontiac, and Scion vehicles share similar ABS hardware and can log the same code. Any vehicle with a brake pressure sensor integrated into the ABS system or master cylinder has the potential to set C0142 when that sensor or its wiring acts up.

FAQ

Can I clear C0142 myself with a basic code reader?

You can often erase C0142 with a simple OBD-II code reader, but if the underlying problem isn’t fixed, the code and warning lights will usually come back quickly. A more advanced scan tool that can see ABS data is much more helpful for diagnosing the real cause.

Is C0142 an ABS sensor or a brake pressure sensor problem?

That depends on your vehicle. On many GM and Toyota models, C0142 is tied to the brake pressure sensor circuit. On others, it can be associated with wheel speed signal issues. Checking the factory description for your year/make/model and looking at accompanying codes will point you in the right direction.

How serious is C0142 for everyday driving?

For normal dry-weather commuting, the car will usually feel fine, but you’re missing ABS and stability control. The real risk shows up in emergency stops or slippery conditions, where ABS and traction control can prevent skids and loss of control. It’s serious enough that you shouldn’t ignore it.

Can a weak battery or alternator cause C0142?

Yes, low system voltage or unstable charging can confuse the ABS module and trigger false or intermittent codes, including C0142. If you’re also seeing dim lights, slow cranking, or charging system warnings, test the battery and alternator as part of your diagnosis.

Do I need to reprogram the ABS module after fixing C0142?

Usually you don’t reprogram the module just for this code, but many vehicles require a calibration or relearn after replacing the brake pressure sensor or ABS module. This is done with a capable scan tool and teaches the module the correct baseline readings so it doesn’t keep flagging a fault.

C0142 – Lateral Acceleration Sensor Circuit High