2002 Chrysler Town and Country headlights will not come on

had a prob with lights and security system a while back. now the head lights will not come on at all. everything else comes on and works, ie parking lights and such. we were told that the body computer is the fault, but are reluctant to pay to have it replaced without knowing the actual cause.
has anyone ever seen this before? Whats the fix?
let me know.
thanks