I wired my 1994 van for my camper lights so i could pull my camper. but as soon as i turn the key on.my tail lights come on and won't go off until i turn the key back off

You have to get a trouble light or meter, you are going to have a wire for 1, brakes 2, tail lights, 3 Left turn, 4, right turn.

need so check ground wires. start at your head lights and fallow the wire harness til you see a wire grounded to the body. check and make sure connections are good and that the wire isnt broken anywhere

may have a defective headlight switch or a bad relay for rear lights..

Are you sure you tied into the factroy trailer wiring circuit of the truck? It is really hard to mess this up.

You are talking about interior lights, right ?
As long as the on-time is under a minute or two, its normal.
The lights are supposed to go off as soon as you start the van tho.

Assuming you have a good battery there is a small wire that goes to the battery terminal on the starter (big red wire) That is where you get power to ignition switch. this is a fusable link wire If you pull on it slightly and it streches it is burned into.Resist the urge to replace it with a non fuseable wire, it is at any parts store

Pull that fuse or pull tail lamp relay, that should kill the lamps till you figure out the problem? You also have left an right tail lamp fuses, underhood fuse box. I don't know if tail lamp relay is faulty? Another concern, see the bottom wire on left of tail lamp relay, that is a ground controlled by the headlamp/multifunction switch, there could be a problem with that wire circuit or the multifunction switch. At the moment, I'm hoping just faulty relay.

Hello,

This is a serious issue. First of I would not even drive this until you you check this out or have it checked out. Wires if burnt on the passenger area. Is most Likely a wire that goes under that area that taps into your rear lights. Meaning this, you have a fuse panel, and your head lights are all tap into that as well as shoots off to your rear lights. So that when you turn off or on your lights it of course suppose to turn on or off the tail lights. So you have two things to look at. Your fuse panel, and find the wire that has got hot and melted. But please don't drive it as it could get worse and cause a fire. Mike

replace the bulbs in the tail light, they are 2 stage, one for parking light and one for brake/signal

Look under the dash, follow the brake peddle untill you find a switch, it's the brake light switch, try adjusting it (it moves in and out of a plastic insert, may take a little pressure to move) there should be two wires that connect to the switch, when the brake peddle is not in used the switch breaks the circiut, push the button on the switch, brake lights should go out, if not, check for power, replace if nessasary