The brake light switch is assembled on a bracket at the top of
Brake Pedal and operating the brake lights at the rear end of the car when the brake pedal is pressed. To check the switch, press the brake pedal and the brake lights should come on and should switch off when the brake pedal is not pressed anymore. If lights do not come on, be sure brake pedal is properly positioned, and then position switch so that there is a gap of 0.025 to 0.076 millimeters between switch plunger and the pedal stopper without forcing the plunger, then locknut is tightened and clearance is again checked. If this produces a false reading then it could be that the switch is not getting voltage or could be defectivewitch can be tested for voltage by and using a multipole test light or a voltemeter voltage should be present at the switch connector with the pedal at rest at one terminal and when the pedal is pressed voltage should be present at both terminals. This is a perfect signal that the switch has gone bad, and no voltage should be felt at both terminals when the pedal is depressed. To replace the switch, the electrical connector must be disconnected, the locknut must be unscrewed, the switch must be taken off and a new switch must be installed, and then fastened tightening the locknut and adjusting the brake pedal and the switch as appropriate.