1999 Lantra - which fuse is for the reverse lights

My 2000 Hyundai Elantra has 2 reverse lights. check out
http://www.paulstravelpictures.com/Hyundai-Elantra-Tail-Light-Bulbs-Replacement-Guide/index.html

loofk for DRL at the fuse box . probably blown- or busted.

Have you checked under the hood in the engine compartment? I do believe there is a fuse box there with fuse for the brake/reverse.

LOOK INSIDE FUSE COMPARTMENT AT BACK OF PANEL YOU SHOULD LIST OF FUSES AND THERE RELATED CONECTIONS .

The sensor on the shifter-to-tranny linkage may be stuck. May need to be replaced

If you have current to lamps Check the earth wires also bulbs and bulb holders for corrosion dirt etc

you need to adjust the switch on the gear selector

there is a gray block fuse under the hood that could control the light
take it out and take it to auto zone and have checked this good be the
easiest fix but it will cost about $25.00 for that fuse!

are the rear lights combined? ie sidelamp and brake lamp in one bulb .if so, there is a possibility that the bulb is not sitting correctly in the holder , causing both the side & brake lamp fuses to blow . if they are seperate bulbs you probably have ashort in the sidelamp system somewhere but the brakes could be a switch problem [easy check, find switch ,disconnect wires short across using wire or paperclip switch on ignition and check lights ] if they work the switch is the problem , [check fuse first] if they don't

You have a bad O-ring seal in the valve body of your transmission. The reason you barely move when you rev high, is because the trans fluid isnt going to the correct part of the valve body due to the bad seal. This should be a repair you can do yourself if you have any mechanical experience, OR a transmission shop may be able to rebuild the valve body for you.