Headlight relays

[dogstar]

well, ive been puttering around the last few weeks, collecting parts, and this weekend i finally bought another set of H4 housings.

just installing them with stock bulbs made such a HUGE difference over my old scratched housings it was worth it instantly.

i also ordered some bulbs from one of the local bike shops.

55/100 watts, low/high, compared to 55/60s.
$4.95 each.


but, now comes the question.

how can i run my headlights through relays?
i want to do this so that i can upgrade my wiring to 12 gauge all the way from the battery to the headlights.

as you all know, or should know, the supra uses quite thin wiring and its got long runs... this leads to voltage drops.

ive been looking at some diagrams, here:
http://www.dorikaze.com/showthread.php?p=82581#post82581
and here:
http://www.danielsternlighting.com/tech/relays/relays.html

ive also got the 82 electrical wiring diagram, the relavent info is here:
http://photobucket.com/albums/a26/dogstarcorsair/relays/



so... heres what ive got done.

i went and got a relay holder, and two hella 30 amp relays.
they come with two 87 pins.
i use one for high beam and one for low beam.
each one has one 87 pin dedicated to left and right sides of the car.
these are wired with the 12 Gauge wire, and ready to install, assuming ive got it right.

i also have two spare headlight plugs, and im pretty sure ive got them figured out, so theyre matched up with the wires off the relays.
but here comes the first question.

does the wire which would normally come off the headlight plug and go back to the headlight motor go to ground now??

and do those wires which come from the headlight motor go to the relay?

as for the switching input on the relay, i believe that i use the factory wires which used to go to the headlight??

i think the former headlight power wires go to pin 86 on the relay, and the wires from the motor goes to pin 85, making this a ground switched system?
someone correct me if im wrong please.

thanks in advance for the help, off to the part store for some connectors.

[batmobile]

`1

[MWebber]

Bat... he said he ALREADY has that stuff... why would he go buy more? you did READ his post... right?


dogstar,

I didn't go look through all the links, but, if you can leave the motors alone, (which you should be able to easily) and connect the respective wires to the coil side of the relay you should be set.

IE: original low beam --> coil of relay, other end of coil to ground. battery to one pin on relay(switch) and the other to the light, then light to ground. repeat for high beam.

This will drastically reduce the strain on the original system by just running the coil on the relay and not 55+ watt light bulbs.

don't forget to put new fuses inline with the new wires off the battery. car-b-q's suck!!!

Mike

[dogstar]

got a fuse here ready to install.

ok, so the three wires coming off the headlight are (obviously) high beam, low beam, and ground.

but now i ask, why is the ground connected to the headlight motor?


and bat, the stuff on ebay is generally plastic lensed shit.
they scratch easily, and are known for cracking at the seam where the reflector is glued to the lens.
plus they have a HORRIBLE beam pattern, which generally blinds other drivers more than anything else.

trust me, been there, done that.
either bosch or hella housings are infinitely superior, with glass lenses and housings.
very strong, and excellent beam pattern.

[MWebber]

got a fuse here ready to install.

ok, so the three wires coming off the headlight are (obviously) high beam, low beam, and ground.

but now i ask, why is the ground connected to the headlight motor?


I looked at the diagram and the lights and motor are grounded at the same place.

You can use that to ground the lights if you wish, or, better yet, cut(edit: off the light plug) and tape (edit: on the motor side) that wire and ground (edit: light plug) back to the battery on lights with a 12 gauge wire or better.

"WB" white w/ black tracer is almost ALWAYS ground on Toyota.

Mike

[Angkistrodon]

Watch that stocker headlight plug......it tends to melt with the slightest increase in draw.
All I did was swap out the sealed jobs to the replacable bulbs types(PLUG:rallylights.com)...same wattage....and they melted on me......3 or four times.

[KesekiSupra]

ive been running 80/100 hella h4's e-codes for like 3 months now, no problems here. stock wiring. but do post pix when u do this? would like to see how its done

[dogstar]

ah, thanks mike, i was havin trouble reading that diagram... must have been too late for me, lol.

ive been running standard E codes for almost two years now on the stock plugs, although i AM using new plugs from napa.
i figure if im running new wires, nice new uncorroded plugs are probably a good idea.

ill try to take pics tonight, but i gotta finish some drafting for a couple clients, and i gotta package some more header panels.

for what its worth, i played the high beam game with a corolla last night, parked nose to nose and fired up the highbeams.
both cars have the standard bosch E code housings, standard bulbs.
hes relayed, im not.

his are brighter...
for now.

[Supra_devil]

Old lights
http://img.photobucket.com/albums/v281/dogstar82/highold.jpg
New lights
http://img.photobucket.com/albums/v281/dogstar82/highnew.jpg
Relays
http://img.photobucket.com/albums/v281/dogstar82/S5300005.jpg
Wiring, no thats not the finished install, lol
http://img.photobucket.com/albums/v281/dogstar82/S5300006.jpg

[Supra_devil]

So barry did this (he has H4's to start) , I am SO DOING THIS to my car, Best lighting mod. available for the $20 in parts and a couple hours of time.

I'm thinking of doing this to my car (sealed beams) to see the difference that way too.

[drftsupramk2]

I would really like a write-up and a price list on this I have thought of dong this but I want to do it right. I seen the ebay ones but was a little scared, relay wiring instructions would be great.-Larry

[dogstar]

its REALLY simple... i was way over complicating it when i was looking at the diagrams.

parts list, ill try to work on, i dont have the part numbers for the hella relays i was using.
hella does offer a kit that includes two 30 amp relays and a twin relay holder, but i managed to find a holder in a local surplus shop.

the wiring i used was 12 gauge.

the relay holder had some clips which needed crimping to my wires.

i went to a local parts place and bought a sealed beam plug with pigtail for the connections to the headlight... mistakenly i thought i had bought two, but one was a different style, so ill have to go back and get the right one.

from there, its really really simple.
run three wires to each light; Low, High and Ground.
both low wires go to one relay, and both highs go to the other relay.
ground goes directly to battery, or another good ground point.

its 5 am and im bushed, ill try to post a better description tomorrow.
very simple mod if you think it through tho.

total cost, including H4 housings, 55/100 blubs, relays and wiring was around $130 canadian.
for just the relays and wiring, $20-30 depending on local sources.

[flyingbrick]

Here's what you want. Really easy to hook up and gets the job done. http://www.4crawler.com/4x4/CheapTricks/Headlights.shtml#HarnessTypes

[Supra_devil]

thats exactly what he did, but he made it himself.

except for a lot less than 50 USD.

[dogstar]

thats a nice clean harness, but i can make mine just as clean for about the same cost.
it is a good option for those who are willing to spend the money for a plug in solution.

on the other hand, i know exactly what components went into my harness, all high quality stuff.

[lechner]

IMPORTANT NOTE: Although this is good info for a 1982 Supra, it does not work on a 1985. In 1982, power to the headlights is supplied throught the dimmer switch and ground is constant. In 1985, power to the headlights is through a relay controlled by the headlight on/off switch; and the ground is through the dimmer switch. One or the other of the high/low wires is always grounded through the dimmer. This means the 1985 system is both Power Switched and Ground Switched instead of one or the other. The good news is the power side is already relayed and 16 awg. The ground side is 18 awg and could use a couple relays for a more direct ground path

[Funkycheeze]

if both the power and ground are switched, you can use a DPST relay (dual pole, single throw) with the switched ground and power hooked up to the coil, and the ground on the 'new' plug along with a good chassis ground to one of the poles. then you hook up a good fused power source from the battery to the other pole along with the +12v on the 'new' plug and you are good to go

[85supra_ftw]

You also aught to remeber that if some jerk cop gets pissed off with you your running OFF ROAD ONLY lights and they can and sometimes will impound your car on the spot. :bananas:

hate to rain on your parade but here in DFW the city of north richland hills has discovered this fact and is impounding cars with wrong headlights, no cats, too low, ect and the $750 impound fee is really what they are after but as its a federal standard it will apply to everyone here in the US. :bananas:

[Supra_devil]

what off road only lights? h4's are perfectly legal and factory equipped(although not on our cars), and i'm pretty sure that running new power and ground wires to the lights isn't considered off road either. This mod can also work with factory lights as well.

[dogstar]

im also in canada, lol, DOT rules are mere rumors to our cops.

we can run pretty much whatever we want for lights as long as they "arent dazzling to other drivers" which i find is more an issue with aiming, and as long as they arent colored bulbs.
other than that, there are only a few laws governing them.


anyways, im still working on putting together a nice write up... im also redoing my harness, this was a proof of concept, and a good experience.
the next one will be molded and heat shrunk, with waterproofing and dielectric grease on all the contacts, few other little changes.

[stevrock]

im also in canada, lol, DOT rules are mere rumors to our cops.

we can run pretty much whatever we want for lights as long as they "arent dazzling to other drivers" which i find is more an issue with aiming, and as long as they arent colored bulbs.
other than that, there are only a few laws governing them.


As he said, the laws are only suggestions, and you're only getting crap if you get caught.

The lights, I have never seen anybody given a problem about them, be they the yellow and pink fog lights to the blueish headlights.