Noticed my dash lights flashing. One headlight was out. No running lights.

Replaced my headlight switch. Left the plug as is. Lights are the same. Still broken.

F-150 4×4 5.8 E4OD 1994

 

Flashing dash lights may be a sign of a short in the wiring. May want to take a look back there. I always start by checking fuses when something electrical like lighting doesn't work. Did you check the fuses? Next thing I check are the bulbs. Just a thought.

 

I have time to look tomorrow. No fuse check yet. But did that a few weeks back. Before the lights went wonky.

Might be a good idea to replace the plug for the switch?

Not sure where a short would be. Any particular known trouble spots on these trucks?

 

Put in a new; Headlight switch & Plug.
Checked all the fuses.
Number 4 fuse was blown.
Replaced #4. But it blew when I tried the running lights.

Where should I look next?

 

Check to see if someone has HACKED in a trailer connector... That is a good source of trouble, people like to cobble them for some reason....

 

Looks like the previous owner did just that.
Will do some snipping and check. Thanks. Will let you know.

 

It works now, but it needed one new headlight. New 15 amp fuse in #4 slot. Plus I switched a wire. When I wired in the new plug. So the dash lights are always on. Unless I pull #4. Still working that one out.

 

Found the wires I switched. All works as it should now.

This form is such a great resource. Thanks mostly to you all who give your 2 cents. Thanks!

 

Just a suggestion to help prevent this in the future. When purchasing a used vehicle, I always open the fuse box and look under the dash and check for any signs of tampering in the wiring. If i see something messed with and the owner claims to know nothing about it, I will go down a bit on my offer.

 

Indeed. This jerry rigged wiring for a trailer. It was much too long. So it kept getting caught in the tailgate. After many times of it getting pinched. It shorted out.