Having problems with one brake light. If I cut on the parking lights all is fine, if I step on the brake the second filment does not light. Turn signals work fine. Does this sound like the brake light switch ? Is there a way I can test a new switch without disconnecting the old one ?
I had a similar problem, it turned out to be the turn signal switch. This happens because they are wired together, if the turn signal switch is bad in one direction then it will affect your brake lights. Try wiggling on the lever in both directions while stepping on the brakes, and have someone look at the brake lights while you do this. If it is that they will see the brake light flash on and off while you do this. Good Luck