well, you can try to see if your plug came loose, the main harness plug when you turn on your lights, and when you signal. maybe your connection there became loose?? you can check there.
thats what happend to my b13. it drove me nuts, no blown fuse, power still running to the lines, but my headlights wont come on. then i finally took my steering column cover off to see if my plug is loose, and sure enough as soon as i took it off, it just fell apart. and i just stuck it back in and all my lights work fine. so yeah, maybe that might be it. hope this helps.