* Faulty Wheel Speed Sensor (WSS): This is the most frequent culprit. The WSS measures the speed of each wheel, and the ABS and TC systems rely on this information to function. A malfunctioning sensor sends inaccurate or no data, triggering the warning lights. This is often accompanied by a slightly pulsating brake pedal.
* Low Brake Fluid: Insufficient brake fluid can activate the warning lights, as it compromises the ABS system's ability to properly modulate brake pressure. Check your brake fluid reservoir.
* ABS Module Failure: The ABS module is the "brain" of the system. Internal faults within the module can lead to the warning lights illuminating. This is usually a more expensive repair.
* Faulty Brake Light Switch: While less common, a faulty brake light switch can sometimes interfere with the ABS and TC systems.
* Wiring Issues: Damaged, corroded, or loose wiring in the ABS system can disrupt communication and trigger the warning lights.
* Faulty ABS Pump: Though less frequent, a failure in the hydraulic pump itself can result in the illumination of these warning lights.
* Low Battery Voltage: In some cases, a very low battery voltage can cause the warning lights to illuminate.
What to do:
1. Check the brake fluid level: This is the easiest and quickest check. Low fluid is a serious issue that needs immediate attention.
2. Have the car professionally diagnosed: The most reliable way to determine the exact cause is to have a mechanic, preferably one specializing in automotive electronics, use an OBD-II scanner to read the diagnostic trouble codes (DTCs). These codes will pinpoint the specific problem.
3. Don't ignore the lights: Driving with these lights on means your ABS and Traction Control are not functioning. This significantly reduces your safety in emergency braking and slippery conditions.
Ignoring the problem could lead to reduced braking performance and increased risk of accidents. It's crucial to get your Impala checked promptly.
