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Headlight issues - bad ground?

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Old Feb 17, 2009 | 05:54 PM
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Default Headlight issues - bad ground?

I've come across a problem lately, I thought my two low beams were blown because they would never come on. So I bought two new bulbs, and now all lights come on including the high beams at the same time.

I've searched and concluded it could be a bad ground, but I don't know where the ground is. I know it's at the radiator support, but I can't find it?

Anyways, suppose it is a bad ground? What should I do?
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Old Feb 17, 2009 | 06:11 PM
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The connectors on the old headlights had some black **** on this, could the mess up the connectors from the headlight harness?
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Old Feb 17, 2009 | 08:13 PM
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So the highbeams come on even if they're not engaged? A bad connector could def be the issue
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Old Feb 18, 2009 | 02:42 PM
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anything else?
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Old Feb 18, 2009 | 10:39 PM
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The high and low beams are switched by whats called a dimmer switch, which I believe is located under your steering column. What that switch does is take a power signal from your headlight relay, and send it either to the high beams or low beams. From there there are 2 sets of wires for the high and low beams, low is a brown color and high is green. Each headlight has its own ground, which goes to the radiator support. You can find each of these by looking just behind the headlight assembly on either side, it should just be set in with a screw.

I would guess that if your low and high beams come on together, that your dimmer switch is bad.
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Old Feb 19, 2009 | 12:03 PM
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Originally Posted by TireSm0ke
The high and low beams are switched by whats called a dimmer switch, which I believe is located under your steering column. What that switch does is take a power signal from your headlight relay, and send it either to the high beams or low beams. From there there are 2 sets of wires for the high and low beams, low is a brown color and high is green. Each headlight has its own ground, which goes to the radiator support. You can find each of these by looking just behind the headlight assembly on either side, it should just be set in with a screw.
There are three wires at each headlight assembly - yellow for lowbeam power, light green for highbeam power, and black for ground. Both headlights on the left side ground to a bolt on the left side of the radiator support and the headlights on the right side ground to a bolt on the right side of the radiator support.

Originally Posted by TireSm0ke
I would guess that if your low and high beams come on together, that your dimmer switch is bad.
Firebirds always run the lowbeams when the highbeams are on. Unlike Camaros, the lowbeams are on whenever the headlights are on and only the highbeams switch on and off from the dimmer switch.
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Old Feb 19, 2009 | 04:03 PM
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But the high beams and low beams only come on together when I put the new bulb in
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Old Feb 19, 2009 | 04:07 PM
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Originally Posted by DrewSG
But the high beams and low beams only come on together when I put the new bulb in
Then I guess replacing the bulb made it work. All 98+ Firebirds have all four lights illuminated when the highbeams are on.

If the highbeams go on/off and the lowbeams stay on when you use the dimmer switch then you don't have a problem - the system is working as it should.
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Old Feb 19, 2009 | 05:36 PM
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Originally Posted by DrewSG
But the high beams and low beams only come on together when I put the new bulb in
What happens when the lights are both on and you pull the highbeam switch?
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