Attn: Ford Techs - Headlight Problems

[GTVertY2K]

HELP. My headlights won't come on.

I have a 2000 GT Convertible.

Parking lights, fogs, turn signals, tails, brakes all work fine.

Pull the switch out all the way and fogs turn off, headlights don't come on and High Beam indicator on dash comes on.

Flipping between high/low beam does nothing.

ANY ideas??

 

[n0v8or]

The high beam indicator and fog lamp cutout are the key clues. Take a good look, and I think you will find the headlights on but very dim. The low beam and high beam filaments are operating in series, because the ground connection has been broken. This could be within the bulbs (unusual), at the socket (most likely), or in the ground wires (the black ones) to the sockets.

It is unusual for this to happen to both sides at once. Each side has a separate ground wire.

 

[GTVertY2K]

Thanks n0v8or.

Yeah, unlikely that both would go at the same time.

I tapped into my headlight switch a long time ago to install NRAuto E/L gauge face plates. Think that may have something to do with it?

 

[n0v8or]

For the electroluminescent gauges, I would expect you tapped into the Blue/white stripe (panel illumination) or Brown (park lights) wire. I cannot see how a problem in the headlight switch wiring could cause the conditions you described; maybe I'm missing something obvious.

Turn the headlights on at night (low beams), and check if they light dimly.

 

[YardSpecial]

Multi-function switch is bad. (wiper stalk)

Very common part to go bad.

I have changed hundreds of them at Firestone.............

 

[GTVertY2K]

Thanks for the replies guys. Late yesterday, turned on lights. now one light works (seems to be on highbeam) and the other is barely on. I was looking at the schematics and thought it may be the "multifunction switch".

CAVALLO, How do I check/replace this switch? is it located INSIDE the wiper stalk?

 

[n0v8or]

So the problem is now intermittent (comes and goes).
If the multifunction switch is the cause, and is intermittent, then moving the lever and tapping around the switch should have some effect. The switch is mounted at the inner end of the stalk. Remove the lower steering column trim cover, and you should be able to see it. Make sure the connector is tight.

I still think, based on your description, that you have a grounding problem, since the multifunction switch uses a single wire for both low beams and another wire for both high beams. Therefore, a multifunction switch problem should affect both lights equally.

It is possible that you have two different problems simultaneously.

 

[GTVertY2K]

Well, it was not the multi function switch. Turns out the headlight socket(s) were fried. I had put high wattage bulbs in when I first bought the car 2 years ago and they finally fried. Had to replace both sockets. Never gonna use high wattage bulbs again. Thanks for your help guys.

 

[n0v8or]

Hi wattage bulbs are OK if you install the ceramic sockets that can survive the heat.

 

[YardSpecial]

Its the WIREING not the socket that heats up..........

 

[n0v8or]

The ceramic sockets come with 8" of high temperature wire already attached, with a plug the mates to the factory connector.