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Discussion Starter #1
I read in the manual (if all else fails, read instruictions), that only in the Canadian version of my '95 DeVille do the headlights come on ay 50% power for daylight driving visibility, same as my '96 Buick (U.S. version).

Are there any kits or home brew work arounds so that I can have the headlights at 50% during normal dylight driving for extra visibility by others (lots of elderly folks with bad eyesight here in Florida)?
 

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It can be done yourself, but would require a lot of wiring. I'll try to give you a brief description of what it entales.

2 diodes
2 resistors (to get 50% power to headlight)
2 relays one for each headlight
A Good understanding of a cars electrical system

First, you will need to make the relay, engage with the car running, i.e. your ignition switch. Then you must have the relay kick off when the headlights are turned on. Thats basically it. If you can get a photo cell, you can actually make it all automatic, but that would involve more work. I can provide the wiring for that as well if you need that. But for now i will just explain the relay setup.

Relay contacts

86 (Red) 12v ignition

85 (black) positive side of headlamp (cut the wire and connect to
firewall side)

30 (yellow) Fused constant 12v

87 (brown) resistor inline, then connect to positive headlamp bulb side wire

87A (orange) Positive headlamp wire bulb side

What this does is activates the headlamps at 50% power when the ignigtion is turned on and the headlamps are off. Once you turn on the headlights, the relay closes back up and the lights work as normal.
Enjoy
Frank
 

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Discussion Starter #3
ultravorx said:
It can be done yourself, but would require a lot of wiring. I'll try to give you a brief description of what it entales.

2 diodes
2 resistors (to get 50% power to headlight)
2 relays one for each headlight
A Good understanding of a cars electrical system

First, you will need to make the relay, engage with the car running, i.e. your ignition switch. Then you must have the relay kick off when the headlights are turned on. Thats basically it. If you can get a photo cell, you can actually make it all automatic, but that would involve more work. I can provide the wiring for that as well if you need that. But for now i will just explain the relay setup.

Relay contacts

86 (Red) 12v ignition

85 (black) positive side of headlamp (cut the wire and connect to
firewall side)

30 (yellow) Fused constant 12v

87 (brown) resistor inline, then connect to positive headlamp bulb side wire

87A (orange) Positive headlamp wire bulb side

What this does is activates the headlamps at 50% power when the ignigtion is turned on and the headlamps are off. Once you turn on the headlights, the relay closes back up and the lights work as normal.
Enjoy
Frank
Thanks for the info. Can you send me a schematic? From what you describe it sounds like a winner. It must require a whopping wattage resistor given the power disipation required to drop, say 3 to 6 volts at multiple amps. I'll just have to wait for your generous offer of a schematic. I don't need the photocell circuit since there already is one as part of the regular system. Then again, it would be helpful to have since the headlights are "turned on" by that curcuit and it would be good to know how that control circuit should integrate with the basic "50% power" circuit you describe. Thanks again for your help and look forward to your schematic (I guess you can attach it as a file to your reply).

Frank H
 

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Here is the wiring schematic you requested. Its all done in paintbrush, that was the only tool i have here at work, but you should have no problem at all following the directions.
Frank

p.s. the diodes were not needed, after i re-evaluated the wiring.
 

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Discussion Starter #5
ultravorx said:
Here is the wiring schematic you requested. Its all done in paintbrush, that was the only tool i have here at work, but you should have no problem at all following the directions.
Frank

p.s. the diodes were not needed, after i re-evaluated the wiring.

Thanks. Are these relays the existing headlight relays on the car or somethings I need to get at Radio Shack or Car parts place? 85 goes to the hot (+12v) side of the low beams? Is there a connection to ground from the relay that is not shown?

Thanks again. Looking to put it together and give it the ole smoke test.
 

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frankh said:
Thanks. Are these relays the existing headlight relays on the car or somethings I need to get at Radio Shack or Car parts place? 85 goes to the hot (+12v) side of the low beams? Is there a connection to ground from the relay that is not shown?

Thanks again. Looking to put it together and give it the ole smoke test.
These relays can be found at any radioshack, pep boys, autozone, circuit city, etc.

The 85 does go the 12v hot, because when the lights are off, that wire will show ground, and with 86 being on ignition, this will activate the coil. When the headlamps are turned on (Low beam setup) this will activate 12v and shut off the relay and your light will be as normal.

P.s. If you cannot find a resistor of that size, there is another way to hook up the lights, so i will post that as well. I didnt realize it may be VERY hard to find a resistor of that size!
Frank
 

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Discussion Starter #8
ultravorx said:
Here is the setup for no resistors, using lowbeams.
Ah yes....Much more elegant solution. If one has to dissipate energy, might as well usae it to make light through the low beam (desired effect) than make heat (through 60W resistors). Thanks for the diagram. It'll be some time before I can have the car long enough to make such modifications. Once I do it (or burn up something under the hood) I'll let you know what happened.
 

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Ooops...

Hate to destroy the hard work here....GM has a DRL kit available for maybe $30. It can be retrofitted to any GM car. Check with your dealer.

Logan
 
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