Headlights stopped working

1994 FORD THUNDERBIRD
100,000 MILES • 4.6L • V8 • AUTOMATIC
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NATEFLA321
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Car listed above is the LX model. First left bulb went out then right bulb, changed light bulbs work for 5 miles then headlights turned off. parking lights still work. cleaned and made sure grounds are all good connections. Still no headlights. I'm wondering if there's any common problem with headlights with these vehicles. if anybody could help I would definitely appreciate it! TYA
Jan 16, 2021 at 11:44 AM
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JACOBANDNICKOLAS
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Hi,

Does the vehicle have daytime running lights? Also, do they work and then stop again?When they fail to work, is it both high and low beam?

If you look at pic 1, it shows this is a basic design, so we need to first, confirm that there is no power to the wiring at the lights. If there isn't, move back to the dimmer switch to check power at the wire I circled in pic 2.

Let me know what you find. Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring



Joe
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Jan 16, 2021 at 8:14 PM
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NATEFLA321
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it has switch to go from parking to high beams the parking lights work the headlamps not work on high or low. I changed the ball they worked fine then went off after a few miles. haven't been able to get them on since cleaned all connections that I could see. there's no relays fuses look good. I'm just wondering what else I can do or how to diagnose this problem? thank you so much for your quick reply. I'm more than appreciate it just trying to help a family member in need.
Jan 17, 2021 at 10:17 AM
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NATEFLA321
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The headlamps went out first one then the other changed bulbs went out within a couple miles. checked fuses made sure all the grounds were connected properly. it does not have a relay the parking lights work but the headlamps do not and they both shut off at the same time with new bulbs in them. if somebody could please help me to figure out to diagnose a way to fix this or I'm thinking there may be a common problem in this model connection wise and the electrical system? if so it would be a great help to anybody who can help or give any feedback.
Jan 17, 2021 at 12:03 PM
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JACOBANDNICKOLAS
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Hi,

I suspect it is the switch itself. In the early 1990's and older, many of these vehicles had an internal circuit breaker in the switch.

So, what needs to be done is this. Go to the switch and confirm there is power to it. Look at the attached pics. Following my arrows, power goes to the switch via the orange / white wires. Confirm there is power. Next, with the lights on, check for power from the red/yellow and let me know what you find.

Also, let me know if this has DRL, automatic lighting, and so on.

Take care,
Joe
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Jan 18, 2021 at 12:58 PM