Problem with speedometer and other weird electrical issues
I have a 2000 F-350 all stock. started it up this afternoon and noticed speedometer wasn't working stayed at 0, as I drove it noticed that the OD was blinking, looked up what might be the problem and saw that it was probably just the rear differential speed sensor so I replaced it and still nothing.so I figured id check the fuses, went to take the fuse cover off to get to the fuses in the cab and started hearing a relay clicking like crazy, got the cover off and it was the lowest relay on the left believe its in the 5 slot. when the key is off the air will blow and you can hear a noise coming from up above the brake pedal, almost sounds like something sizzling like loose wire or bad connection. when I take the #22 fuse out the noise will quit but the air will still blow. not really sure whats going on, starting to think I got some kind of wiring issue but don't know where to start. Anyone ever had this happen? how do you fix it??