1. Check the brake light bulbs: Make sure that the brake light bulbs are not burned out. You can do this by visually inspecting the bulbs or by using a multimeter to test them. Replace any burned out bulbs.
2. Check the brake light switch: The brake light switch is a switch that is activated when you press the brake pedal. If the brake light switch is not working properly, the brake lights will not come on. You can test the brake light switch by disconnecting it and checking for continuity with a multimeter. If there is no continuity, the brake light switch is faulty and needs to be replaced.
3. Check the brake light wiring: Check the wiring that connects the brake light switch to the brake lights. Make sure that the wires are not damaged or corroded. Repair or replace any damaged or corroded wiring.
4. Check the brake light relay: The brake light relay is a component that controls the power supply to the brake lights. If the brake light relay is not working properly, the brake lights will not come on. You can test the brake light relay by swapping it with another relay that has the same part number. If the brake lights work with the new relay, the old relay is faulty and needs to be replaced.
If you have tried all of these steps and the brake lights still do not work, you should take your vehicle to a qualified mechanic for further diagnosis and repair.
