So I’ve owned my ‘’92 W250 for about 2 1/2 years and have been having electrical issues (among other things) the entire time.. I’ve been in friends shops trying to figure it out, countless hours on this forum, testing the best I can with multimeters, etc. Going across country I will blow almost 50 fuses.. Its really making me furious and is actually straining my relationship as I spend so much time researching and talking about it and now I have to borrow GF’s car most the time. Symptoms seem to worsen in winter.. I have cleaned grounds and chased wires for endless hours,.. replaced : multifunction switch, brake light switch, rear sockets, and attempted to undo both trailer hook-ups and brake controller. I have put something to hold brake pedal and tried wiggling wires to no avail,.. fusible links appear fine. I can almost hear a static buzz sometimes from inside the cab that sounds like electric static or something.. have read about steering column causing short.. but also think scramble of trailer wire in rear could be culprit. Any help is really appreciated and please be kind as this is my first post on DTR (I tried doing my homework before posting).

Steve

1992 W250 Getrag 360 5.9 6bt

Seems ya’ll like photos around here

Thank you for quick response. My truck is base model , so no power windows etc. Gonna check this door wiring when the sun comes out in couple of days though.

So stop lamp fuse blows, turn signal and hazard fuses. Brake blowing the most as thats used the most. I hear ya on the fusible links only “looking ok”.. seems to be common and also where my buddy thinks I’m having issuses.

Ohh and wiring appears fine behind fuse box. The steering column plastic was removed and fuse box hanging down with no plastic piece to hold it up under steering column when I got the truck.. had been sitting in barn in California for years. I feel like I’ve picked up someone elses headache they never figured out.

Ok so I had first sunny day in a week, started poking around and tried this first. Had to make it to town for some hay and had my brake and turn fuses blown, so decided to take 20amp fuse for hazard and use it for brake lights. Didn’t make it to end of long driveway before I saw smoke coming from multifunction and/or fuse box.. was hazard depressed from last time I messed with it? I’m not sure..Pulled another 20 amp and put in hazard fuse spot, popped immediately.. now my brake wire looked melted behind fuse box! (And gf’s car has hay everywhere haha). Looks like big blue sitting for awhile.