Either a fuse ( located behind panel below steering column, pull from the top) or the switch on the brake pedal.
I would prob be heading towards the the switch.. did they start not working now and then????? Cause mine did the same and it turned out to be the switch.. It turned out the Holden were cheaper the switch was $13 dollars from Holden or $16 from repco. When you refit the new make sure you dont screw it in too far otherwise they still wont work. from the bottom of the switch to the pedal assembly it has to have up too 5 mm gap.......
mine did this not long ago and it turned out to be the brake switch located behind the brake pedal. its easy to fix and not too expensive either....
