I will start with the basics. I have parking lights that stay on all the time. I have to disconnect the battery when I park for more than a few hours. My park lights are on all the time, but get slightly brighter when I turn them on with the headlamp switch. This is the first annoying part. Now, my headlights are coming and going. When driving, it will get a hot electric smell, the headlights will go off and then come back on. So far, I have not been stranded, just nervous.

Now the paul harvey version..... (and now, the rest of the story)

I was driving to work one night, about 15 miles into my 2 hour commute, I lost all my running lights, tail lights, dash lights, front marker lights. My headlights still worked, and brake lights work, as well as emergency flashers. No big deal, the fuse was blown. Change the fuse, which is in kind of a crappy place, and off I went, about 50 foot into my drive, lights went out again. I changed the fuse 2 more times with the proper amperage only to have it go out again and again. So, fed up and late for work, I put in a 30 amp fuse, figured either I would make it to work or the truck will burn, either way was cool with me. So, I had a burning electric smell for about 30 seconds (inside the cab) and it went away as quick as it came. The only result was permanent parking lights.

My minor troubleshooting was left to a quick look at the headlight switch and removing the wire-harness plug from the switch still left me with energized parking lights. ALSO, I have OTHER EXISTING issues, the passenger side window went down one cold day and never went back up. After wasting a couple precious hours (its not the switch in either door, its not the window motor) I reversed polarity in the window motor and put the window up and unhooked the motor wire. The radio will turn on and off, voluntarily. Sometimes the sat tuner will be present, sometimes it will not.

This is a stock truck, the only aftermarket thing is a factory sirius receiver that I added to my stock radio. The kind that plugs into the factory tuner and mounts inside the dash. There is NOTHING aftermarket on this truck, nothing broke, nothing modified. This is a pampered, dent, ding and smudge free truck that is kept in a heated and air conditioned garage. My bad for taking such good care.

I have about absolutely NO time to trouble shoot this problem. I am more likely to trade it in (paid for) than I am to spend hours looking for a short. If this is something other than a common module, I will pull the fuse and take it to the dealer.

 

Okay first off these are all guess but I think they are all separate issues.

Constant Parking Lights
There is definitely a short in the wiring somewhere but you probably knew that. When I looked up your symptoms about this in the shop manual it says to first pull wiring plug from the headlight switch, which you did, and see if that turns off the lights. Then if the parking lights continue to stay on it says, if you DON'T have autolamps to repair circuit 14 (BN). If you DO have autolamps it says to disconnect Vehicle Security Module C3008a. If then the lights go off to check the connectors for corrosion and pushed out pins.

So can see circuit 14 BN is a pretty big circuit. There could also be an issue relating to the trailer tow lighting circuitry but not sure.


You can see Vehicle Security Module C3008a here. The module is located on the back cab wall on the drivers side.


Window stuck down
I remember reading others had a similar problem but I don't remember their solution. I had this happen on another car and it turned out to be a broken wire in the door.

Radio turning on randomly
This sounds like somethings faulty with the radio power switch. I've never torn one apart but it's probably fixable. But it's even easier to find one from the junkyard.

It could be a simple fix for the parking lights or something more indepth. I'm sure others here can help you better on this.

 

Jeff, it sounds to me like you have wire 195 in the schematic that was posted is shorted to wire 14 in the harness. That would explain why you could unplug the switch and the lights stay on. The power is crossing from 195 to 14 without going through the switch.
What likely happened is that the something on circuit 14 went to ground and when you installed the larger fuse the circuit got hot enough to melt the two wires together, and I would venture the other troubles your having are related to the same damage in the harness.
There are tools to find opens and shorts in a harness without having to open up everything. Power Probe makes a very good kit to find shorts and opens even behind interior panels. It can even show you which way the ground or short is in the circuit.
I hope this helps, good luck in finding the trouble.