If the wiring is the same on the saphs, brown is earth (looking at the plug its the one on the right) The other two are dipped and mainbeam I think the top pin is dipped.

There will be two small white (or sometimes blue) relays in the fuse box for the dipped circuit and mainbeam. Double check these arent burnt out or miss connecting. (not usually a problem on the sierras but are on the escort / orions!)