1. Check the Brake Pedal Switch:
* Location: This switch is usually located on the brake pedal assembly itself. It's a small switch that's activated when you press the brake pedal.
* Testing: With the ignition OFF, visually inspect the switch for any obvious damage. Then, carefully disconnect the electrical connector from the switch. If the brake light goes OFF, the switch is faulty and needs replacement. If it stays ON, the problem is elsewhere.
2. Check the Brake Lights Themselves:
* Burnt-out Bulb: A burnt-out brake light bulb can sometimes cause the other brake light to stay on. Check all three brake lights (two on the rear and one on the center high-mounted stop lamp/CHMSL). Replace any burnt-out bulbs.
3. Inspect the Wiring:
* Visual Inspection: Carefully examine the wiring harness leading from the brake light switch to the brake lights for any damaged, frayed, or corroded wires. Look for any places where wires might be shorting to ground or each other.
* Continuity Test (Advanced): If you have a multimeter, you can test the continuity of the wiring. This requires disconnecting the wires at various points and checking for a complete circuit. This is a more advanced troubleshooting step.
4. Check the Fuse:
* Location: Consult your owner's manual for the location of the fuse box and the fuse that controls the brake lights.
* Inspection: Visually check the fuse for any signs of being blown (a broken filament). Replace it with a fuse of the same rating if necessary. A blown fuse could indicate a short circuit somewhere in the system.
5. Check the Brake Light Switch Connector:
* Often, corrosion in the connector can cause the brake light to stay on. Carefully inspect the connector for corrosion and clean it with contact cleaner.
6. Consider the Integrated Control Module (ICM) (Less Likely but Possible):
* In some vehicles, a faulty ICM could contribute to this issue, though this is less common. This requires more advanced diagnostics.
7. Ground Issues:
* A poor ground connection somewhere in the brake light circuit could also cause this problem. This requires inspecting ground points and ensuring they're clean and making good contact.
Important Considerations:
* Safety: Driving with a brake light constantly illuminated is dangerous as it may not alert other drivers to your braking intention in an emergency. Fix this problem as soon as possible.
* Professional Help: If you're not comfortable troubleshooting electrical systems, take your S-10 to a qualified mechanic. Incorrectly diagnosing and repairing electrical issues can lead to more damage.
By systematically checking these points, you should be able to identify the cause of your persistent brake light. Remember to replace any faulty components with the correct parts.
