Have you replaced the bulbs yet? They are double filament bulbs. So, the running lights can work and the brake light filament will not. It tends to burn out first as it glows brighter and hotter.
If it is not that check the fuses and lastly the relay.
September, 4, 2012 AT 10:20 PM
Just to add to this one if the high mount bulb works the fuse is good or that one wouldn't be on ethier. Also have you ever had the brake light campiagn done on that car?They had tons of issues with tose bulb sockets so free of charge saturn was replacing the sockets.I have done tons of those campaigns.