Found this forum looking for answers for my issue. Hopefully someone can help me out here..
My issue is my running/parking lights stay on after turning engine off. The only way to turn them off is by disconnecting the battery.
1st thing I did was clean and replace bulbs in marker lights. They are now all working but the front yellow ones are dimmer then the rest. Still didn't shut off.
2nd Pull headlight switch. Lights didn't shut off.
3rd Put a new 4way trailer plug in. Still won't shut off.
4th Changed the Headlight switch connector. Still won't shut off.
5th Changed the Headlight switch. Still won't shut off.
6th pulled the fuse for the marker lights. They finally shut off but not the running lights.
7th pulled some relays. running lights still on.
Please help if you can. Thanks!

 

The problem I had was on a 1989 F350 Dually. When I turned the lights off the marker lights came on, when the lights were turned on, the marker lights turned off. The problem was a relay.

 

I did notice the light switch getting hot rather quickly. Maybe that just cause it was out and I could feel the heat. I have herd that the relay maybe stuck. My problem is that I need to figure out what relay it would be. I thought that by pulling them I could narrow it down. I'll search a little. Thanks.

 

I believe its one of these in the power distribution box but I'm not sure which one. print is to small.

 

Looks like Horn, Blower, fuel pump, and EEC. Anybody know where the Relay would be for the Running/parking lights. Or if this could be my issue. Really need this fixed any help would be grrrrreeaaT!

 

This thing is really driving me bonkers! The more I read the more confused I get.
Its gotta be down to the relay or a grounded out wire somewhere.
Ok, so I pull a 10 amp fuse in the power distributer box and the clearance /marker lights go off. Now just the running lights are on. Anybody know where the fuse is for that?

 

There is no relay. Sounds like there are some wires melted together. One thing you could try is look under the hood, there is supposed to be a fuse box under there somewhere. Inside it is a 10 amp fuse for the trailer running lights. You could pull this fuse and see if the lights go out. If they do, you know the problem is with the trailer circuit.

If it's not in the trailer circuit, the only other choice you have is to start unpluggin harness plugs, or unplug other fuses one at a time. Unplugging harness plugs till the lights go out will give you a clue where the location of the problem is in the harness. Unplugging other fuses will tell you where the stray power is coming from, and that might give you a hint where to look.

 

Thanks for the input Dave F. I was hoping you might chime in. The 10 amp fuse that I pulled that shut the marker lights off may have been the one for the trailer/running lights. Now I just need to find the one for turn/running lights I guess. Thanks! I'll keep looking!

 

Turn lights are a separate circuit, nothing to do with the running/marker lights. Your brake/turn lights are staying on also?

 

Well Dave another satisfied customer! You are da man.
I found my issue tonight. After all the BS it was an aux plug behind the drivers seat. It has all the same color wires that go to the headlight switch. CORRODED! three pins were corroded together. My guess< Spilled BEER! Capping plug. Thanks everyone. See you at Crandon

 

Help I have no tail lights or instrument lights, fuse are good brown/ white wire coming out of fuse box has no power

 

I don't know what model you are working on, but more than likely the tan/white wire is burnt in two somewhere between the switch and the fuse box. Double check the taillight fuse, that's where the tan/white comes from.

 

Sorry it's a 2005 6.0 f250

 

I didn't read your post very carefully. You have no power on the wire over near the fuse box or near the switch?

 

Here's a diagram.