I have a 98 suzuki marater and my tail light is out but my brake light works changed bulb still nothing how could this be.

check your bulbs because the tail lights are twin element one for lights and the other for brake lights. Probably the lights element is broken and only brake lights are working. The other possibility is either the tail light fuse or relay not working.

try changing both bulbs each bulb has two wires in it, sounds like a wire has burnt out in both the tail light wires are first to go they are thinner wires

did you change the bulb?
does head light work?

The circuit to the taillight brake bulbs goes through the turn signal switch. Sometimes the switch can cause this problem.

does the high mounted brake light work? the brake switch has 2 contacts one for the high mount (LT BLUE/BLACK) and one for the tail brake lights. The tail/brake light wire is LIGHT BLUE. the main connector between the brake light switch and the tail lights is C208 which is located behind the rear seat, left side. So if there is power coming out of the brake switch OK and no power at the tail lights, check that connector. Hope this helps.

It might be a dual element bulb. One element can still function while the other one is out. Take the tail light cover off and look at the bulb. If one of the elements has a broken wire, then replace the bulb.

p park position should only light the tail light, so my guess is there is one filament of the stop tail bulb shorting to the other filament inside the bulb, try a new bulb

Open the Back and unscrew the tail light screws on the inside of the door jam. The whole tail light assembly will come out. Twist the bulb socket counter clockwise, pull the bulb out. Place new bulb in the sockett, place sockett back in tail light and turn clockwise till it stops. Place tail light back in hole, put screws back in to door jam to hold tail light in.

Resolution Below -

Okay, I had the same problem...My 04 Suzuki DR200SE tail light /brake light is not working. Brake lights works in park mode not in ON with engine running or not. Tail light not in either mode.

Volt meter shows the socket is working correctly, fuses are good. I even adjusted the pressure switch for the rear brake application. MOM shows nothing positive to help me trouble shoot and neither does the internet. Lots of people with same issue, but I'm not seeing any resolution.

I'm posting the resolution as lots have had this issue, but no one has posted how they fixed it. It's the ground wire inside the tail section. Which is why the volt meter (which is grounded) shows the socket is good. You'll have the pull the tail section and note the ground wire has either broken off, or the wire has sucked up inside the insulation. You'll need to strip insulation, get to good wire and reattach it. I'd even solder it to keep it solid. Hope this helps someone else!!

Check the brake light fuse. The high mounted brake light (third brake light) is on a different circuit than the brake lights. Hope this helps.