Most Likely Causes:
* Low Brake Fluid: This is the first thing to check. Low brake fluid suggests a leak somewhere in the system, which is a serious safety hazard. Top off the fluid (carefully, using the correct type), then look for leaks around the calipers, wheel cylinders, brake lines, and master cylinder. A low fluid level *can* trigger both lights.
* Brake System Malfunction (Independent of ABS): Even if the ABS system is fine, a problem with the regular braking system (like a worn brake pad sensor, a seized caliper, or a bad wheel cylinder) can cause the brake light to illuminate. The ABS light then comes on because the ABS system detects an imbalance in wheel speed.
* ABS Speed Sensor: One or more of the ABS wheel speed sensors might be faulty, dirty, or damaged. These sensors monitor the rotation speed of each wheel. A malfunctioning sensor can trigger both lights.
* ABS Module/Control Unit: The ABS module itself could be failing. This is a more complex and expensive repair, often requiring professional diagnosis and replacement.
* Brake Pressure Switch: The brake pressure switch (often located on the master cylinder) tells the system if the brake pedal is being pressed. A faulty switch can cause the brake light to stay on constantly.
Less Likely Causes (but still possible):
* Wiring Issues: Damaged or corroded wiring in the brake or ABS system can cause intermittent or constant illumination of the lights.
* Master Cylinder: A failing master cylinder could be the underlying cause.
Troubleshooting Steps:
1. Check Brake Fluid Level: This is the absolute first step. Low fluid indicates a leak – a serious safety concern requiring immediate attention.
2. Inspect Brake System: Visually inspect brake lines, calipers, and wheel cylinders for leaks or damage.
3. Check Brake Pads: Worn brake pads can trigger a warning light (though usually only the brake light, not both).
4. Code Scan: Use an OBD-II scanner to read any diagnostic trouble codes (DTCs) stored in the vehicle's computer. This will often pinpoint the exact problem. An ABS scanner might be necessary for more detailed ABS system diagnostics.
5. Professional Diagnosis: If you're not comfortable performing these checks, or if you can't identify the problem, take your van to a qualified mechanic for a proper diagnosis and repair. Driving with these warning lights on is risky.
Safety Warning: Driving with a malfunctioning braking system is dangerous. If you suspect a brake system problem, have it inspected and repaired immediately. Do not drive the vehicle until the problem is fixed.
