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Discussion Starter #1
Since I've gotten my car back from the shop, I have been low on money after paying for the body shop invoice. I don't have enough money for some new tires or an alignment which is what the car needs to get back on the road, but I probably can focus on little things for now. One of the little problems I need to focus on are the headlights. I haven't been able to get them to work or turn on ever since I got the car. Even with a new battery, they won't turn on. I also checked for any gnawed off wires in the engine bay just in case, but found nothing. This leads me to believe that it wasn't a rodent related problem. Any ideas on what it could be?
 

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Do any of the exterior lights work? If they do then the headlight switch is receiving power from the battery.
Pull up the carpet on the driver's toe board and unplug the 3 wire connector from the headlight dimmer switch. With the headlight switch in the On position do you have power to the wire in the middle? That wire brings power to the dimmer switch. The other 2 wires are for power out of the switch to Low and High beam.
 

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You didn't mention the year. This is a schematic for a 69. All the classics are very similar as far as the schematic goes, but that doesn't mean they are wired the same. A schematic shows how it works, and a wire diagram shows how it is wired. You are going to need a wire diagram for your year, as a schematic doesn't show wire colors or where connections are made. Don't expect all wire diagrams to be accurate- I found three versions for a 66 or 67 that were all different.
The light circuit starts at the top left. The light switch is connected directly to the battery. It has internal circuit breakers and an on-off switch which goes to the dimmer switch. If you don't have a 69 you won't have four headlights- just disregard the added lights and the other versions are the same.
 

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First place I'd look is the dimmer switch. You should have power coming in on one wire and going out on one of the remaining two wires. When depressing the switch you should have power coming in on the same wire but going out on the other wire. If you only have power coming in on one wire you can unplug the dimmer switch and jumper that terminal to the others and observe the lights. If they now work, replace the switch.
 

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Discussion Starter #5
I've found out the problem! The headlight switch was unplugged from the connector. I didn't notice this before, but glad I found out. Seems like the headlights switch itself was broken. To make a long story short, the courtesy light in the cabin stayed on even with the switch supposedly turned off, both courtesy light door switches off, and the keys out of the ignition. Now that I found the main culprit, I need to take out the switch and replace it.
Do any of the exterior lights work? If they do then the headlight switch is receiving power from the battery.
Pull up the carpet on the driver's toe board and unplug the 3 wire connector from the headlight dimmer switch. With the headlight switch in the On position do you have power to the wire in the middle? That wire brings power to the dimmer switch. The other 2 wires are for power out of the switch to Low and High beam.
The exterior lights do not work with the switch plugged in. I checked the connections to everything at the front valence and they are in good condition. The switch itself wasn't plugged into connector. When I fiddle with it, it felt broken and didn't work at all. Turned it on, head lights still didn't work. But, when I closed the doors, turned the ignition to off, the courtesy light stayed on. This leaves me to believe that the unit is getting power, but the switch itself is broken.
 

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Discussion Starter #6 (Edited)
You didn't mention the year. This is a schematic for a 69. All the classics are very similar as far as the schematic goes, but that doesn't mean they are wired the same. A schematic shows how it works, and a wire diagram shows how it is wired. You are going to need a wire diagram for your year, as a schematic doesn't show wire colors or where connections are made. Don't expect all wire diagrams to be accurate- I found three versions for a 66 or 67 that were all different.
The light circuit starts at the top left. The light switch is connected directly to the battery. It has internal circuit breakers and an on-off switch which goes to the dimmer switch. If you don't have a 69 you won't have four headlights- just disregard the added lights and the other versions are the same.
Sorry for not responding, the year is 1970. I have a schematic for all the exterior lighting, etc in a book I have. I already have consulted it.
 

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Discussion Starter #7
Do any of the exterior lights work? If they do then the headlight switch is receiving power from the battery.
Pull up the carpet on the driver's toe board and unplug the 3 wire connector from the headlight dimmer switch. With the headlight switch in the On position do you have power to the wire in the middle? That wire brings power to the dimmer switch. The other 2 wires are for power out of the switch to Low and High beam.
When the switch was plugged in, the courtesy light in the car itself worked by itself without the doors being open or turning it onto accessories. When the headlight switch wasn't plugged in, the courtesy light in the doors didn't stay on after ignition was turned to off and doors closed.
 

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Discussion Starter #8
First place I'd look is the dimmer switch. You should have power coming in on one wire and going out on one of the remaining two wires. When depressing the switch you should have power coming in on the same wire but going out on the other wire. If you only have power coming in on one wire you can unplug the dimmer switch and jumper that terminal to the others and observe the lights. If they now work, replace the switch.
I have power going into the headlight switch unit itself, but not to the headlights. Only power I get from the switch is for the courtesy light on the ceiling. When I had the switch plugged in again, doors closed, and ignition to off, the ceiling courtesy light stayed on. From this, I know that the unit itself is getting power, but just needs to be replaced.
 
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