My headlights started blinking...

[Handegard 10]

I've been told this was a common problem with the switch...

 

Should I replace the switch on the dash, or the highbeam switch on the floor?

 

I've been meaning to find out for awhile, my truck does the same thing, but it never gets driven at night, so it hasn't been a big deal...

[rwcstang 201]

hrm check the switch or it could be a bad ground of some sort.

[J's69Mach1 17]

I think your headlight switch Needs to be replaced.

[ForceFed70 14]

Headlight switch. Have you swapped to halogen headlights? If so, you may want to install a relay for the headlights. If you install the relay, you might not have to put in a new headlight switch.

[69togo 10]

You need to put in a relay or relays. I had the same question and replaced switch after switch and still had flashers for headlights. Do check the ground though but my experience resulted with relays. There is an article in Mustang Monthly just on 69 headlights. Google it and you'll find the step by step process of putting in the relays and H4 halogen bulb. After that you can run all four lights at once with no problem.