Hey Scotty, I got a 2007 Ford Ranger Sport, 3.0L V6, Automatic (5R44E) 2WD with 194k miles on her and the headlights would intermittently flicker fast and when the headlights are flickering the fog lights will not turn on, and sometimes the brights won't work, I changed the main light switch, multifunction switch on the steering column (Cause someone said they had that happen on a mustang and it fixed the issue) and I've changed the main headlight and fog light relays and it still happens, what could be the issue and how can I resolve it cause it's frightening to drive at night and the lights start flickering? Thanks!
could be corrosion or heat damage in the connector
Check those 17-year-old grounds.
I cleaned and wire wheeled every ground wire I could access including the body to frame ground using all data for the locations but it still happens, I checked the connectors to the main and multifunction switch for corrosion or signs of overheating and nothing was seen, side note it can happen on first startup or while driving so the overheating isn't the cause, what are some other things I could check?