Possible Causes:
* Low Brake Fluid: This is the simplest and safest place to start. Check your brake fluid reservoir. Low fluid can indicate a leak somewhere in the system. Top it off if low, but only with the correct type of brake fluid for your vehicle (consult your owner's manual). A leak needs to be found and fixed immediately.
* Brake Light Switch: This switch is activated when the brake pedal is pressed and triggers the brake lights and often the ABS light as well. A faulty switch can cause intermittent issues. Relatively inexpensive to replace.
* ABS Sensor(s): These sensors monitor wheel speed and are crucial for the ABS system. A dirty, damaged, or failing sensor can cause the ABS light to illuminate. They're located near each wheel. These require specialized tools to properly diagnose.
* ABS Control Module (ABS Pump): The ABS control module is the "brain" of the system. Internal failures can cause intermittent or constant light illumination. This is the most expensive component to replace.
* Wiring Issues: Damaged, corroded, or loose wiring within the braking system can cause intermittent problems. This is difficult to diagnose without a wiring diagram and a multimeter.
* Wheel Speed Sensor Ring: Located on the wheel hub, this ring is read by the ABS sensor. Damage or corrosion can interfere with the signal.
Troubleshooting Steps (Proceed with caution!):
1. Check Brake Fluid: This is the first and most important step. Top it off if needed but look for leaks!
2. Visual Inspection: Look for any obvious signs of damage to brake lines, wiring, or sensors.
3. OBD-II Scanner: An OBD-II scanner can read diagnostic trouble codes (DTCs) from your vehicle's computer. These codes can pinpoint the likely source of the problem. This is a relatively inexpensive tool you can purchase or have a parts store scan your vehicle.
4. Brake Light Switch Test: You can usually test the brake light switch with a multimeter to see if it's functioning correctly.
What NOT to do:
* Ignore the lights: Driving with a malfunctioning ABS system is risky. The ABS is a critical safety system.
* Attempt major repairs yourself without experience: Incorrect repairs can lead to brake failure.
Recommendation:
Due to the safety implications and the complexity of the ABS system, taking your Suburban to a qualified mechanic or a brake specialist is strongly recommended. They have the diagnostic tools and expertise to accurately identify the problem and perform the necessary repairs. Ignoring this could lead to a dangerous situation.
