If this is a full size Bronco, mid '90s, then your problem is most likley in your four way flasher switch, located on top of your steering colum. Both the brake and the turn signal circuits go through that switch. You may be able to prove this by wiggling the switch button around or depress and release the button several times. All lights may still not work but if you see any of them begin to work again then the switch will need to be replaced.