S/4 FC with S/5 tails

So my tails,3rd brake light,parking lights, headlight, blinkers hazards all work fine. Wen i put on my brakes only the passengerside brake lights work, the driverside (BRAKE LIGHT) wont work...
any info would be great
thks jason

 

look at the bulb. its probably blown... and your probalby gonna think (well it works when the lights are on..) but theres 2 wires in the bulb and one may have broke... that was my problem a few weeks ago.

 

ya i lookd at it last nite and saw fillament lookd intact , didnt know they had 2,
thks i changd bulb and works perfect

 

 

glad to help