Not sure, special tool $uck…
Even if the Switch was shorted, it would only turn on the lights not short them out.
What you might do it check the continuity between the power wire and the frame and see if it might be shorted.
Pull the wire off of the Trans Switch and check between each end of the wire and again from the plug to the frame.
Another thing might be to attempt to bypass the switch with a piece of wire and see if the light work with out blowing a fuse while the truck is sitting still. If they work and run for over your time limit then it might be the switch. Make the jumper with good connections and drive around with them on for a while, if they blow then you know you have an intermittent shorted wire, if they don;t blow out then I would replace the switch.
If they blow out while driving, run a new wire, first from the switch to the lights, if that doesn’t do it then from the power side to where ever that goes. (I don’t know where the power comes from, there may be a relay or maybe directly from the fuse panel I do not know, sorry).
Another thought… check the switch to see if when you put the truck in reverse the switch works, then run new wires, relay and tap the backup lights near the rear of the vehicle, cutting as much of the OEM wire out of the circuit as possible. Run a new fused power wire from the battery to a relay to the backup lights and control the relay with the OEM backup light switch.
Tape back all of the wire that you cut out or remove them.
sorry if this is confusing, just ask if you have any more questions, there will be someone on this site that will know more about the OEM Wiring than I do and maybe they will jump in.
4x4, 5sp, Std Cab, Stepside, E4 Red
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