* Low Brake Fluid: This is the most common and often simplest cause. Check your brake fluid reservoir (usually a clear or translucent container near the master cylinder). If the fluid level is low, you have a leak somewhere in your braking system (lines, calipers, wheel cylinders, master cylinder). This is a serious safety issue and needs immediate attention. Driving with low brake fluid is extremely dangerous.
* ABS Sensor Issues: The Anti-lock Braking System (ABS) uses sensors on each wheel to detect wheel speed. If one or more of these sensors is faulty (damaged, dirty, or improperly connected), it can trigger both the brake and ABS warning lights.
* ABS Module Failure: The ABS module itself can malfunction, causing the lights to illuminate. This is a more complex and expensive problem often requiring professional diagnosis and repair.
* Brake Switch: A faulty brake light switch can cause the brake light to come on, sometimes triggering the ABS light as well due to the interconnectedness of the systems. This is a relatively inexpensive part to replace.
* Wiring Problems: Damaged or corroded wiring in the brake or ABS system can cause intermittent or constant illumination of the warning lights. This can be difficult to diagnose.
* Master Cylinder Failure: While less common, a failing master cylinder can also lead to this issue.
What to do:
1. Check the brake fluid level immediately. If it's low, do not drive the truck. Have it towed to a mechanic to find and fix the leak.
2. Have the system professionally diagnosed. While some simple checks (like fluid level) can be done yourself, properly diagnosing the cause of the warning lights often requires a mechanic with a scan tool capable of reading ABS codes. The scan tool will identify the specific problem area.
Ignoring these warning lights is extremely dangerous. Brake failure can have catastrophic consequences. Get the problem diagnosed and repaired as soon as possible.
