I have a 2004 Grand Cherokee Special Edition 4.0L I6 AWD, I was driving the other night, sitting at a light I noticed my blinkers quit working (but hazards still did), got home, looked it up and saw the relay was a common problem with solder breaking. Pulled the relay (which looked different inside than the one I saw in the video, assume it was changed by previous owner) put a new one in, didn't fix it. looked online at a fuse box diagram, didn't see anything that would fit my issue but decided to pull them all anyway, fuse 20 was blown. Well on that same online diagram, it said it was the "Ignition Run" which confused me, I checked the diagram actually on the fuse box (kinda hard to see) and it said it was the "HVAC SeatSW". Put a new 10A in, turn signals and everything worked, leaving out of my neighborhood I noticed a red light under the dash (fuses light up when blown) and I had no turn signal or heater controls. went home, put another new one in, it all worked until I tried to leave, tried again and it trips as soon as I take it out of park. tried putting a 15A in, same thing.

Looked up a different fuse box diagram online and this one says that fuse 20 is: "Combination Flasher, Automatic Zone Control Module (AZC), Manual Temp. Control (MTC), Temp. Valve Actuator (MTC), Trans. Solenoid/TRS Assembly (4.7L), Park/Neutral Position Switch (4.0L, 3.1L TD), Driver Passenger Heated Seat Switch"

That one seems more detailed (and accurate with the temp control and flasher listed). I don't know a lot about jeeps (first one and only had it for 6 months or so) the park/neutral position switch sounds like it might be causing it? how would I go about testing that? Is there a common thing that goes wrong with those? If I do need to change it, where is it located and how hard to do?