I was driveing around tonight (with 2 girls and a couple of friends in my car, no less ) and something went screwy with my lights. My headlights are flickering and my side marker lights, dash lights, sport lights, and tail lights will not come on. Everytime the headlights flicker you can hear a click come from the headlight switch. Everytime that happens the dash lights, side marker lights, and tail lights light up for a split second. Did my headlight switch die or something? We went in to eat somewhere for about 45 minutes and when we left the lights worked normal for about a minute and then started flickering again. The headlights work, they just turn off for a split second and when they do the tail lights and stuff come on for a split second. Anyway, that was embarassing as hell and cut our night short since I can't drive around with screwed up lights. One of my friends volunteered to get in the trunk and hold flash lights up to the tail lights.
Your headlight switch has a built in circuit breaker in it. They sometimes get weak and stuff like that happens. The clicking you hear is the breaker. Just change out the switch and you should fix your problem.
Ohh, if you open the door and turn the headlights on, the dome light flickers with the head lights. But if you turn the headlights off, the dome light works normal.
It's actually a pretty common problem with the old Fords. I've changed several of them over the years.
Another thing that will do it is if you add a lot of stuff to the light circuit. I had the dual tail lights and grill lights in my Sprint many years ago that were wired directly in the light circuit. After about 45 minutes, the lights would start cycling on & off. Took me a long time and a few switches to figure out what was happening. I switched the grill lights to a relay and cured the problem.
Only thing thats hooked to the light circuit that wasn't from the factory is the backlight in the tach, temp, oil pressure and volt gauge. I have the Grabber grille from my '74 with the sport lights, but at the same time I also removed the lights down in the front valance because they were rusty and didn't work, so I shouldn't be pulling anymore power there unless the sport lights have bigger bulbs in them or something. The wireing in the trunk of the car is a hacked up mess, I did my best to clean it up and tape it up, but I'm wondering if something may be shorting out back there. I'll try a new switch first and see what happens.
It seems like after all this years Ford still has a problem with this. The same thing has happened on two of my Thunderbirds. On my Super Coupe the factory fog lights are on the same circuit, so we put a relay on it. Mavaholic's idea with the relay is probably one of best long term solutions.
that happend to me years ago i was driving down hwy and they flashed on and off all the way home glad i did not get pulled over it was not fun
Yea, I was takling to my dad about it the other day and he told me about back in the late 80's, him and my uncle were driving my grandpa's '70 428 Cobra Jet Cougar XR7 down here from Indianapolis when the headlight switch went bad. He said people kept pulling off to the side of the road because they thought my dad was flashing his headlights at them. I haven't changed my switch yet, but I haven't had any more problems out of it. I drove the car to NC and back in the dark yesterday (200 miles round trip), and the lights worked just fine. I think I'm going to change the switch anyways just to avoid future problems. I'm willing to bet the switch is original and this car has at least 136,000 miles on it, possibly 236,000. The title I have has the mileage listed as 228,000 when someone in VA sold the car in October 2001.
