MY HEADLIGHTS AND TAIL LIGHTS WENT OUT, I WAS TOLD IT WAS A RELAY FUSE,

Question edited for clarity.
Question moved to model category.

tail lights don't need relays as the amperage is very low. Only headlights and fog lights use relays.

https://www.google.com/search?q=1993+Nissan+Pathfinder.+Where+is+the+tail+light+relay

Fuse Box diagram

https://www.google.com/search?q=1993+nissan+pathfinder+fuse+box+diagram

..

no car told
not one clue, year,maker or model
Tail spark, parks go to 4sides 4 corners and lic, lamps. 10 lamps.
even more with parks on mirror L/R

on newer cars there is no fuse,
they use BCM, the body brain.
and it uses smart electronic regulators for lamps
that self correct if the short is cured.
common shorts are, trailer hitch hack jobs.
or collision damage never fully corrected.
MOST BCM slip the park feeds 4 waYS, F/R AND L/R
SO TELL IF ALL 10 LAMPS PARK ARE BAD

THE WORD TAIL WAS FOR TIN LIZZY DAYS, 1 REAR TAIL
AND NOW IS 10 PARKS. OR MORE.
NO CAR TOLD OR I'D OF POSTED THE SCHEMATIC TO IT.

Check the tail light bulbs & marker light bulbs.

PERHAPS IT HAS A RELAY FOR THEM UNDER THE HOOD

Fuse #2 10A in underhood fuse box. Also, there's a tail light relay. Check that as well

I had this problem with my 2007 Honda CRV -- all the lights worked EXCEPT the tail/running lights and the license plate light. The other tail lights worked -- brake, reverse, indicators, and hazards. Front headlights also worked, but when the headlights went on the back tail lights did not (not to safe for driving at night!!)
The fuse was #15 in the interior fuse box (under the dash driver side) with the label "small exterior lights" ( also check fuse #19 labeled "small lights main"). The cause of my problem, I believe, is a bad or lose wire in my license plate light.

I would recommend finding the fuse and check it first, then find and check the headlight relay, one of these must be faulty. Good luck and Happy New Year!

The relay has nothing to do with the tail lights, but replacing the switch sounds like a good idea. There's a nut holding it in place, see http://www.skandix.de/en/spare-parts/electrics/switches/switch-headlight/1027524/ to get an idea of the construction. And the price. This is not worth fiddling about unreliable workarounds...
In addition, if fuses 15 and/or 16 burn frequently there might be a problem with the tail light cabling.

Good luck
Ingo

Your tail lights work off a fuse called park lights. No relay involved. Do you headlights come one. Please go premium so I can get paid for info. If ths has helped, please post as such.TY