04 chevy duramax crew cab possibly possessed
 

Ok so about 2 weeks ago my brothers truck decided to act like it was possessed locking itself whenever it wants to then just started locking ever 5 seconds we've replaced the relays and fuses still does the same thing with or without the key in the ignition and with or without the truck in gear the truck has the auto lock feature when put in and out of gear I'm out of ideas where to look has any one else had this happen and what to did you have to do to solve the issue

My best guess is that there is a bad door switch somewhere and has some soda pop or water spilled in it shorting it out. Go through and unplug each door lock switch in the arm rests and see if the problem stops - replace the bad switch to fix it. I suppose it could be part of the gear selector switch on the side of the transmission too.

Basically, unplug the stuff that can actuate the power locks and see what makes it stop. If nothing makes it stop, start going through wiring. There's also probably a module somewhere for door locks.

I'd say the master switch in the drivers door is bad. The rest of the switches should only lock individual doors.

Come to think of it his driver door lock works half assed and I'm sure he has spilled "soda" on it a few times so that's the next step this weekend goin thru his door switches then the gear selector

Good call.

I vote for "Possessed". Face Detroit and bow deeply three times.

Quick update on this we had to reset the security settings by pushing a lot of buttons and turning misc. things on it worked for about a month and still doing the same thing

Did you replace the switches?