test your high low beam switch. also double check to make sure that the high isn't blown out on both headlights
Please don't use a piece of wire in place of a fuse like what the other person mentioned. You can do massive damage like a fire if the problem isn't corrected and you hook up both sides of the fuse panel with a piece of wire.
Don't know Nissans at all, but all of my Fords have a relay for the low beams & a separate relay for the high beams. In my daily driver Mercury, these relays are on the driver's wheel well under the hood.
Nissan B-13 is a very old car, still i have one. check both the bulb filament, in this car one bulb is having both high and low beam filament. one bulb is having three legs. if they are right check the fuses that you have mentioned. if the fuses are right check the connection on the bulb holder, remove and replace the bulb.if fuses are not right replace it, if not available use thin wire to connect the both legs of the fuses. hope this will solve your problem. still if you cannot make it by yourself take help of mechanics.
They were working fine till today. I doubt it's a fuse problem cos if it was one, even the low beams won't be working. I believe they share the same fuse.....they do right? (H/Lamp LH and H/Lamp RH fuses ).
Can someone who knoows about these stuff help me?
Thanks :)