Why Is My Traction Control & ABS Brake Light On?

Seeing a Traction Control & ABS Brake Light illuminate on your dashboard can cause worry. However, in most cases, it simply indicates a minor problem that can be easily addressed. In this comprehensive guide, I’ll draw on my expertise as an automotive technician to explore the most common reasons the traction control and ABS brake lights turn on. I’ll also provide actionable tips to diagnose and resolve the underlying problem. Read on for everything you need to know about what to do when faced with this warning light in your vehicle.

Why Is My Traction Control & ABS Brake Light On?

These are the main causes of Traction Control & ABS Brake Light On:

  1. Wheel Speed Sensor Failure
  2. Brake System Problems
  3. Traction Control Module Failure
  4. Low Battery Voltage
  5. Tire Pressure Problems
  6. Bad Wheel Alignment
  7. Dirty Sensors

Wheel Speed Sensor Failure

The most common reason the Traction Control & ABS Brake Light comes on is a faulty wheel speed sensor. Modern vehicles use wheel speed sensors to monitor the rotational speed of each wheel. This data is fed to the ABS module to modulate brake pressure during hard stops. It’s also used by the traction control system to detect and mitigate wheel slippage.

If one or more wheel speed sensors fail, it will trigger the ABS and traction control warning lights. Here are some key points for diagnosing and fixing wheel speed sensor issues:

  1. Inspect sensors and wiring for damage – Wheel speed sensors can get coated in debris or be physically damaged by road hazards. Inspect sensor condition and ensure wires are intact.
  2. Check for sensor resistance and voltage – Use a multimeter to ensure the sensors are providing proper resistance and voltage. Consult a repair manual for specifications.
  3. Replace damaged sensors – If a visual inspection reveals damage, the sensor will need to be replaced. Fortunately, wheel speed sensors are relatively inexpensive.

Replacing a faulty wheel speed sensor will commonly resolve ABS and traction control lights if they were triggered by a sensor issue.

Brake System Problems

Since the ABS system relies on proper brake hydraulics, issues in the brake system can also trigger the Traction Control & ABS Brake Light. Here are some brake-related problems that could cause the lights to illuminate:

Low Brake Fluid

Insufficient brake fluid will impede proper ABS operation. The brake fluid reservoir should be checked regularly. If it is low, carefully top it off with the recommended brake fluid specified in your owner’s manual.

Caution: If the fluid is abnormally low, have the brake system inspected for leaks immediately. Driving with low brake fluid is hazardous.

Air in Brake Lines

Air trapped in the brake lines will compress when pressure is applied, leading to a soft brake pedal. The ABS relies on firm brake pressure and will turn the warning light on in response to excessive air in the system.

Bleeding the brake system to remove any air will help restore proper ABS function. This involves draining the brake fluid from each caliper while refilling the master cylinder reservoir until the new fluid flows smoothly with no bubbles.

Brake Line Damage

Physical damage like crimps or leaks in the brake lines will also affect hydraulic pressure on the calipers. Carefully inspect brake lines for any damage or corrosion. Damaged sections of the brake line will need to be replaced to restore ABS function.

Faulty Brake Pump

The brake pump builds pressure in the ABS hydraulic control unit. A bad pump will be unable to properly modulate pressure to individual wheel calipers. Replacement of the faulty pump is needed to correct the issue.

Traction Control Module Failure

The Traction Control & ABS Brake Light may indicate an internal failure of the traction control module itself. This control unit constantly monitors wheel slippage and adjusts throttle and brake inputs to maintain control.

If the module suffers an electrical or mechanical failure, it will turn on the warning light. Diagnosis of the traction control module involves checking for stored diagnostic trouble codes, electrical faults, and proper actuation during wheel slippage events. A failed module will require replacement by a professional automotive technician.

Low Battery Voltage

Since ABS and traction control operation relies on electrical power, a weak car battery can also trigger the Traction Control & ABS Brake Light.

Have the battery tested to confirm it is still holding a proper charge. Recharge or replace the battery as needed to maintain the correct voltage to support your vehicle’s electrical systems.

Tire Pressure Problems

Uneven tire pressure will make the ABS and traction control systems work harder to prevent individual wheel slippage. This abnormal wheel speed data can confuse the system and cause it to turn on the warning lights as a precaution.

Carefully check and adjust the inflation pressure of all tires to the placard amount listed inside the driver’s door jamb. Proper inflation will help normalize individual wheel speeds.

Bad Wheel Alignment

Like tire inflation, improper wheel alignment can result in individual wheels spinning at different rates. This will activate the Traction Control & ABS Brake Light due to the abnormal wheel speed sensor data.

Have a professional alignment shop inspect and adjust front and rear wheel alignment to factory specifications. This will help all four wheels rotate at the correct speeds.

Dirty Sensors

Road grime, salt, and debris buildup on the wheel speed sensors can interfere with their signal output. Carefully cleaning the sensors with an electrical contact cleaner or brake parts cleaner can help restore normal operation.

How Do You Clear ABS And Traction Control Light?

The most common way to clear an ABS or traction control light is by properly diagnosing and repairing the underlying problem. Once the fault is fixed, the light will turn off on its own. Some scan tools can also clear codes and lights, but the problem must still be addressed, or the light will just come back on. Avoid techniques like disconnecting the battery to try and reset the light, as this usually does not work. Focus on pinpointing the root cause through proper diagnostic testing.

Can I Drive My Honda With ABS Light On?

You can drive a short distance with the ABS light illuminated in your Honda, but this is not recommended. The ABS may not fully function, reducing braking safety in slippery conditions. Have the vehicle serviced promptly to restore proper ABS operation. Carefully inspect the brakes, fluids, sensors, and electrical system per factory service instructions. Driving extended distances with the ABS light on can risk complete brake failure and should be avoided in a Honda or any vehicle.

What Is The Most Common Cause Of The ABS Light To Come On?

The most frequent cause of an ABS warning light is a failed wheel speed sensor. Over time, the sensors can become contaminated or damaged. This provides incorrect wheel speed data to the ABS module. Other common causes include low brake fluid, air in brake lines, faulty brake components, and worn ABS rings. Proper diagnosis of the specific root cause is key before attempting any repairs.

Can Worn Brake Pads Cause ABS Light To Come On?

Yes, worn brake pads can potentially activate the ABS warning light. As pads wear down, more space is created between the pad and the rotor. This can allow the caliper piston to travel farther forward on hard stops. The ABS module sees this extra piston travel as a fault and turns the light on as a precaution. Replacing worn pads restores normal caliper piston travel and will turn the light off if this is the underlying issue.

Can Low Brake Fluid Cause ABS Light To Come On?

Insufficient brake fluid is a very common reason for the ABS light to illuminate. Low fluid levels or fluid leaks will allow air to enter the hydraulic lines. The compressible air hampers proper ABS operation, triggering the warning light. Topping off the brake fluid reservoir with the recommended DOT brake fluid spec may resolve the issue. However, the root cause of any leaks must still be addressed to prevent brake failure.

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Frequently Asked Questions

Is It Safe To Drive With The Traction Control Light On?

While not ideal, you can safely drive a short distance with this warning light on to get to a repair shop. Avoid aggressive driving and slippery conditions whenever possible.

Will The Abs Still Work With The Light On?

The ABS may still function partially, but you cannot rely on full ABS capability with the warning light active. Have the vehicle repaired to restore the ABS to proper operation.

Can I Reset The Light Myself?

Unfortunately, the Traction Control & ABS Brake Light cannot be reset without completing repairs. The light is tied to fault codes that will remain until the underlying problem is fixed.

How Urgent Are Traction Control Repairs?

It’s safest to have traction control repaired promptly. But this system is considered a supplemental driving aid and less crucial than fixing ABS problems. Still, repairs should not be delayed for long.

Does The Traction Control Use The Abs System?

Yes, most traction control systems use ABS wheel speed sensors and hydraulic components. This is why an ABS fault can also trigger the traction control warning light.

Conclusion

Having your Traction Control & ABS Brake Light illuminated is inconvenient but easily fixed in most cases. With some basic troubleshooting and repairs, you can get both systems back to full function. If you encounter any complex issues, seek out a professional automotive technician for reliable diagnostics and repair. Properly functioning traction control and ABS are important for safe vehicle operation, so never ignore this warning light for long.


Author's Image

Ammar Masoud

I have had a long and fulfilling career in the automotive industry, primarily with Honda and Acura. With 15 years of experience as a Honda service technician, I became highly skilled in repair and maintenance, gaining a deep understanding of these vehicles. After many years in the automotive field, I decided to embark on a second career in industrial manufacturing. It was a significant change, but I found that the skills I had honed in the automotive industry were incredibly valuable in my new role. In my current position in industrial manufacturing, the demand for quality workmanship and meticulous attention to detail is paramount. Fortunately, these are traits that I have cultivated throughout my years in the automotive industry. I take pride in applying these skills to meet the high standards expected in the manufacturing sector.