1993 EX coupe 5spd

when the car is parked with the motor running and the headlights on...all the bulbs function except:

the inner brake lights: the rear driverside is lit up, but it doesn't glow brighter when i press the brake pedal. the rear passenger brake light works properly.

the outer brake lights: do not function when the brake pedal is pressed.



BTW, fuses are good, all bulbs good