Side lights come on when braking? HELP

[luke1]

On my brothers 182, the side lights are coming on when applying the brakes. Checked the rear clusters and they look ok. Any ideas what to look for?

 

[fUbAr]

bad earth somewhere most likely.

 

[luke1]

Sorted it now thanks. Turned out to be a dodgey twin bulb. It wasn't blown but on closer inspection, the filaments had crossed over at the base of the bulb. Thanks anyway.