Why do your blinkers work but not your brake lights?

Blinkers can work without brake lights. Brake lights are activated by a switch that is switched by the brake petal and the turn signals are acivated by your turn signal switch on your steering column. The two are two separate circuits. I suggest you check out the switch on your brake pedal to see if it is working properly. It must have 12 volts applied to one side when it is not acitvated and 12 volts should be on both sides when it is activated. When the 12 volts is on both sides of the brake switch, it should apply 12 volts to your brake lights and then they should come on.