headlight problem
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From: ABQ
headlight problem I replaced both lowbeam headlights less then a month ago, and now they stopped working. Funny thing is though my fog lights, gages, interior lights all still work.... what would cause only my head lights to go out? i've looked for a fuse many times now with no luck.... All my other fuses are good. Some guy with a third gen told me my Dimmer switch could be out adn that could cause the problem? but my dimmer switch seems to wokr fine and control the gages still. My connections behind thwe headlights are fine, nothing shorted out, or old.... I'm confused and need help 
There is a fuse, switch, relay, and bulbs in the system. If you have an electrical tester, I'd suggest testing at the bulbs first. I got a bad batch of Sylvania bulbs in the last year and they both crapped out on me at the same time. (I think I saw a few others with the same issue on this site.)
If there's not juice at the bulbs, you can check the other three. (The dimmer is near the headlight switch, but it shouldn't effect the circuit.
If there's not juice at the bulbs, you can check the other three. (The dimmer is near the headlight switch, but it shouldn't effect the circuit.
Joined: Nov 2003
Posts: 11,328
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From: Jacksonville, FL (originally from Toronto Canada)
There is no fuse or relay in the headlight system. The system is protected by a fusible link (a 6" piece of special wire designed to melt if too much current flows - much like a fuse) under the hood. All the power flows through the headlight switch then the dimmer switch (highbeam/lowbeam switch, not the dash light dimmer) direct to the headlight bulbs.
If your highbeams work then you can eliminate the fusible link and the headlight switch as the source of the problem. It would have to be the dimmer switch, the wiring to the bulbs, or the bulbs themselves.
If your highbeams work then you can eliminate the fusible link and the headlight switch as the source of the problem. It would have to be the dimmer switch, the wiring to the bulbs, or the bulbs themselves.
Thread Starter
Teching In
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From: ABQ
well my high beams dont work either... both of the headlights are newish, they've been on for maybe a month? when you say wieing to the bulbs does that mean starting all the way under my dash? i looked under there and got lost if i remove the siwtch, can i like connect the wires and see if it lights up? or is that a stupid thing to even mention lol
if i remove the siwtch, can i like connect the wires and see if it lights up? or is that a stupid thing to even mention lol Joined: Nov 2003
Posts: 11,328
Likes: 344
From: Jacksonville, FL (originally from Toronto Canada)
Use a test light or multimeter to check for constant power at either of the red wires at the headlight switch. Then turn the switch on and check for power at the yellow wire. If you have power at the red wires but not output through the yellow wire then the switch is faulty. If you don't have power at the red wires then the fusible link is blown or the wiring is damaged.
If you have power output on the yellow wire then you'll need to check the dimmer switch (highbeam/lowbeam). The dimmer switch is near the base of the steering column connected to the ignition switch. It has three connections - yellow, tan and light green. Check again for power on the yellow wire with the headlight switch on. If there's no power then the wire between the headlight switch and the dimmer switch is damaged. If there is power on the yellow but not on either the tan or light green wires (depending on whether it's switched to lowbeam or highbeam) then the dimmer switch is faulty.
If you have power from the tan or light green wires but the headlights aren't working then you'll have to start looking for a break in those wires someplace between the switch and the headlight bulbs.
If you have power output on the yellow wire then you'll need to check the dimmer switch (highbeam/lowbeam). The dimmer switch is near the base of the steering column connected to the ignition switch. It has three connections - yellow, tan and light green. Check again for power on the yellow wire with the headlight switch on. If there's no power then the wire between the headlight switch and the dimmer switch is damaged. If there is power on the yellow but not on either the tan or light green wires (depending on whether it's switched to lowbeam or highbeam) then the dimmer switch is faulty.
If you have power from the tan or light green wires but the headlights aren't working then you'll have to start looking for a break in those wires someplace between the switch and the headlight bulbs.
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Thread Starter
Teching In
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From: ABQ
alright well i tested everything, the red wires got power, but not the yellow one... but after moveing everything around my headlights came on! well as i was putting everything back together they went out again adn wont come back on... could the switch be old and worn out and replaced? if so which switch? the dimmer seems fine so the actaul 3 position one i assume. or do you think there is a short or a wire pinched and got geta solid conection?
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Verdad Gallardo Joined: Nov 2003
Posts: 11,328
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From: Jacksonville, FL (originally from Toronto Canada)
Sounds like the headlight switch. You have power coming into it (red wires) but not going out of it to the dimmer switch (yellow wire) so the switch seems to be the point of interruption.
