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Discussion Starter · #1 ·
Hi there again, but this time with an electrical question.

For as long as I can remember, when using my high beams they may work for a while and turn off. My father says replace the dimmer switch as it was not intended for halogen lights. However after reading some old threads it seems that it could be the switch, the dimmer switch, or the ground. Mind you that the headlights work on low beam 100% of the time, so is safe to rule out a bad ground? I would like to get this problem resolved for this summer...don't want to hit a deer on the way back from the Pottsville Car Cruse weekend.

I also read about installing relays and using the original wiring to energize the coils? I think I know what I need to do, but I am a mechanical engineering student, not electrical (I claim black majic on some of what they say in electrical engineering :rolleyes: ). I work with a bunch of electrical engineers for a large connector company so I have a brain trust to tap into if I am completely stumped.

So the million dollar question is...what to do? Relays or replace the switches, both dimmer and light? If anyone has done the relay mod is it worth it? I like pictures...pictures of how it goes together would be great. I would prefer not cutting into the stock wiring if i decide, get convinced that it best, to use relays. Everything is original on this Gal, or close to it.

Thanks again,
coal cracker
 

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I don't have a diagram for a 66 but if it is anything like my 61 you will have to cut the wiring somewhere to use a relay but it is really worth the effort. Even if you are using stock bulbs you will notice brighter lights using a relay and using Halogens it will likely make a big difference.

My lights were going off on High Beam so I installed two relays, one for high and one for low to take most of the demand off the switch, the dimmer switch and the old original wiring. Now I do all the cars I build even if I am not having an issue.

Scott...
 

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There is a circuit breaker in the headlight switch. Newer Halogen draw more than these can handle and they trip. Also as they age they get more sensitive I've found they can't even handle the original lights on high beam often.

Here's a good site I bookmarked. One thing I don't suggest is a fuse on the headlights as shown. Use circuit breakers. If the fuse blows you're in the dark. The reason Ford used a circuit breaker originally is if they overload they trip and reset and give you some light for a while. I would also have a separate breaker for the high and low beams again so you're not left in the dark! I just used the inline ones you find on modern cars in the junkyard. I did it on my Mustang and it works great and I just used the original wiring to energize the relays. The nice thing is if your switch is old you don't need to replace it as the relays won't draw enough to trip the original breaker. Also feeding your lights almost direct from the battery reduces voltage drop caused by the wire going into the cabin and all the way back which can be substantial (1-2 volts out of 12 is a LOT) That equals brighter lights. It is also safer to keep the higher amperage stuff outside of the cabin too.

Wiring Headlight Relays
 

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Install relays and forget about it. Here's the link to an easy job.

http://www.fordmuscleforums.comgalaxie-pages/482559-brighter-headlights-using-relays.html

But it appears that link is bad! Someone help me out here... It's in the Galaxie pages dating to about February of 2009
http://www.fordmuscleforums.com/galaxie-pages/482559-brighter-headlights-using-relays.html

The / after .com was missing gary.

Coal, if you search 'brighter headlights' there are a ton of threads on the topic.
 

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Coal cracker - if you want to retain original wiring (no cutting), then you would simply un-plug your headlights, and plug each of the connectors into relays and new wires to feed the headlights. This solves two issues - one of retaining the original wiring, and second it replaces the wiring that limits the power to the headlights. As previously stated, the old wiring then becomes just a signal circuit to the relays.

To do this with standard DOT bulbs, you will need two standard relays, headlamp sockets, and appropriate lengths of 10ga wire (solenoid battery stud to relays) and 14ga wire (relays to headlamp sockets), a handful of .250" female spade connectors and one ring connector. I would strongly suggest also placing a 30A auto-resetting circuit breaker in-line from the power source to the relays. In-effect, you are building a new wiring harness, but it will only be from the battery to the headlamps, and not back to the switches and all. You can even skip the headlamp sockets if you insulate the spade connectors and don't mind attaching each one individually rather than a connector block.

If using up-rated bulbs, then beefing the system even more would be suggested, such as in the wiring diagram below. While 10/14ga wires are more than adequate for safety, 8/10ga is to get all possible brightness.

While the relays can be added without the new wiring, it will require cutting the original harness or adding creative jumpers, and will not allow for brighter headlights as you are still running through 45-year-old crappy little wires and crusty connections. All fresh and beefy will give the improvement many speak of. You don't need to run separate wires to all the socket connections, but rather one hi and one low wire with breakouts to each socket as shown in the Rowand schematic and pic below. Also, relay grounding can be right at the relay mount, and the same for the headlamps. This greatly simplifies wiring and effort. Once you have your supplies, the whole project shouldn't take more than an hour the first time.

David

One schematic from an electrical engineer looking for full brightness with minimal voltage drop and up-rated bulbs:
 

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I want to do this with mine one day. I don't even run my brights cause it doesn't make enough difference to matter.
Why not post that in the Work Party thread? It would be a great side-project at the FM BBQ also. A Tech article and/or live web feed from it would be awesome too.
;):tup:
David
 

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Psig, actually did mention it in that one i think. RnR/Ron and I both were interested and think someone else also. Will double check to be sure though as it could be in the main get together thread.

Get a full production setup going! lol Got a small video camera here with gazillion zoom you could see a tick on a deer almost and a tripod. Too bad it didn't have wireless too huh?
 

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Discussion Starter · #14 ·
Thanks for all the info and diagrams guys :D

I have decided to go with relays and be done with it. I picked up two relays, a 30A circuit breaker, and some 12 AWG wire. I will put it together and see what i get. Maybe even do a side by side comparison for others that may wish to see the benefits of this set up. Now its time to head into the shop and get started on this.

Coal Cracker
 

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The easiest place to put the relays is on the inner fender directly under the gap between the hood and the fender ... where the rain comes in :mad:
 

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I had to do some rewiring on my '67 this past spring and decided to install relays for the head lights at that time. My car had an electric fuel pump when I got it that was wired straight to a 12v source without a relay or switch so I needed a relay or two anyway. I picked up a fuse/relay box off a '99 Crown Vic and rewired it to work a relay for the Low beams, High Beams, Fuel pump and one for some added accessories. Relocated the vacuum can to the drivers side and installed the box by the battery on the passenger side.

Of course this meant a bit more wiring running along the firewall to the passenger side, but in the end it functions and looks alright. Made a whole new headlight harness to run from the passenger side over to feed the headlights with new connectors. Wired the box and wiring for the new harness and existing and accessory connections using 4-wire trailer connectors (they kind of look like larger versions of some of the connectors Ford used back then) in case I need to remove it and add anything on later. Using fuses, but this box could accept breakers and I wish I had thought of that rather then fuses for the light circuits. I can always rewire it later.









 

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Fordman, where do you get connectors? I'm cheap but still tired of wirenuts and black tape.
 

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The headlight connectors I picked up at one of the local parts stores. If I remember right it was autozone, but it could have been Advance or O'Reilly. Same with the trailer connectors, I got those at Napa.

For all the splices in the box I soldered and used heat-shrink tubing. I have a large crimp connector assortment (ring, spade, ect) that I picked up from Harbor Freight on clearance awhile back. For anything I add on I've been using those, but I ditch the blue/red/yellow covers and crimp then solder and heat shrink those too. Probably over-kill but I want everything to last.
 

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... Using fuses, but this box could accept breakers and I wish I had thought of that rather then fuses for the light circuits. I can always rewire it later. ...
There are circuit breakers to fit all the various kinds of fuse locations (round, mini-blade, std blade, etc.), so no need to re-wire. Be sure you get the Type 1 breakers (auto-reset) for headlights. To see the varieties available check this out.

David
 
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