Brake lights problem

Can anyone help me with a problem with my brake lights. The rear right brake light (in the bumper) comes on but the other two brake lights do not. I think there is only one fuse for the brake lights so it does not appear to be a fuse problem. If you have any idea what the problem is please let me know.

Thanks

Bulbs blown?

Mine is the same. Bumpers and high level come on, both other don't. Bulbs check OK. Need to trace the wiring back.

You mean the top two lights which are fog light with the reversing lights don't come on pending model your driving. Have you wired the fog lights to the brake lights?

Check for 12v at the bulb holder, and rig a temporary earth.