Hi Guys,
I am dealing with 2012 Ford E350 Gas,which was used in mining before, something happened weird, intermittently my car become a stupid and shiftier stucks, no head light, no cabin light, no power windows and no power locks,... and after 5 or 10 minutes everything comes back to normal, yesterday , I clean up whole fuse box and put new fuse but the same problem,I cleaned up all connectors under driver dash,
I really need your help, even I changed the engine computer too, but still the same problem, please help , thanks

 

There are times when a poor ground supplying the interior systems is questionable and can be under the hood, nowhere near the problem area. These grounds look perfectly clean and good , but have paint under them or some slight corrosion not visable to the naked eye. These darn connections can have enough resistance to affect circuit operation when cold and once they heat up the problem disappears until it cools down again and ,,,,,,,,,,, the reverse can happen where it works fine when cold , but acts up when the connection gets warm and interferes with a clean path .
Before condemning any components, it is always good practice to confirm good grounds and power connections for that circuit. Best to use voltage drop testing to do this.