headlamp relay conversion/upgrade

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landon1
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headlamp relay conversion/upgrade

Post by landon1 » Thu Dec 11, 2008 11:26 pm

thoguht i'd run this one past you guys and see if anyone has tried it to cure dim headlights...

from the diagram, if i'm reading it correctly...you get 2 headlamp relays (one for low, one for high), from them, you run a power wire directly to the battery or alternator. then you splice into the low or high(depending which relay you're working on) factory wire and attach it to the relay. then run wire to each headlamp off of the relay. each relay will also be grounded, as is each headlamp.

supposedly, this bypasses the headlamp switch and dimmer switch routing of the factory harness to let the headlamps (and according to one guy, the heater (???)) run at 14 volts instead of 11 or whatever the voltage drops to.

here's a link - googled diming headlights and this came up - it's also talked about on ford adn chevy forums as well

http://www.moparts.org/Tech/Archive/elec/10.html

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71_DEPUTY
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Re: headlamp relay conversion/upgrade

Post by 71_DEPUTY » Fri Dec 12, 2008 12:02 pm

take the power off the alt. stud- make sure you use at least a 20 amp fuse- water proof type.

the relays allow the main power to go directly to the headlights and not thur a whole bunch of connections- this causes a voltage drop of at least 2-2.5 volts. it will also ease up on the existing wiring, connections and headlight switch. best upgrade that can be done to a old mopar as the headlights are nice and bright!!!!!!!!!!!!!!!!!


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landon1
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Re: headlamp relay conversion/upgrade

Post by landon1 » Sun Dec 14, 2008 7:13 pm

finding relays and other parts online wasn't cheap, so i took a trip to radio shack and picked up more than what i needed for $24....installation was pretty simple, but i forgot my manual, so i had to probe to find which wires were for low, high, etc., but no problem there...spent less than an hour on installing the relays and making better electrical connections under the hood.......it made a drastic imporvement in the lights...before, they kinda looked like candles and now they can about blind you when about 20 feet in front of the car - my LED taillamps should be coming this week and that should allow for some extra relief on the electrical system.

CtownRunner
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Re: headlamp relay conversion/upgrade

Post by CtownRunner » Sun Dec 14, 2008 8:28 pm

Not to hijack but tell me more about your led tail lights?
Image

landon1
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Re: headlamp relay conversion/upgrade

Post by landon1 » Sun Dec 14, 2008 9:08 pm

just replacing the sockets and incandescent bulbs with LED bulbs - i haven't decided, but i'm thinking about removing the stock socket, filling it in, then mounting the sockets in the back of the housings so that the light is projected outward instead of upward. they should draw less power, be brighter, and power-up faster than the 1157 incandescent bulbs...if i'm pleased with the taillights, the plan is to finish off the rest of the lights with LEDs and down the road do an H4 headlamp replacement, but for now the philips halogens are doing the trick pretty well - not sure if i even need the driving lights on there anymore.

sometime this winter/spring i'll be rebuilding the suspension and hopefully sometime next year i'll be able to afford to get a full 2.5" exhaust out the back.

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road chicken
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Re: headlamp relay conversion/upgrade

Post by road chicken » Fri Dec 26, 2008 9:29 am

One thing to note here about the headlamps. If your upgrading to sealed halogens you should up grade the wiring also as halogens have more current draw than the standard units. I think the harness wiring is 18 ga, and you should bump that to 16 ga. Between the relay and the lamps.


With the leds.

You will probabaly have to change your blinker can to a heavy duty unit. When i swapped the front directionals from the LED units, it would no longer blink. Afterwards i found out the LED's do no load the circuit enough to activate the blinker and it acts like you have a bulb burnt out. The HD unit cycles no matter what.
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landon1
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Re: headlamp relay conversion/upgrade

Post by landon1 » Fri Dec 26, 2008 11:58 am

if i remember correctly, the diagram said to use 12, so i used 12 where it said to and 14 everywhere else. teh car had philips halogens that were put in long before i got the car adn they are so much better - amazing difference.

The LEDs aren't working as well as i had hoped - the turn signals blink fine, but i had 1 socket that wouldn't light up on lamp or directional/brakes...and the whole driver's side of the taillamp won't light up, but it will blink and come on for brakes....between my dad (Pops) and myself we figured they woulnd't blink, but that they would come on for just lamps just as you said, but they work on one side, just not the other....

where would i find a HD blinker - just something from Oreilly's? Thanks

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71_DEPUTY
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Re: headlamp relay conversion/upgrade

Post by 71_DEPUTY » Fri Dec 26, 2008 3:52 pm

if it is all leds you need this type

http://www.ledshoponline.com/electronic ... r_cans.htm


if there is a couple of regular bulbs with the leds and it is under 10 amps you can use the same one above!

landon1
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Re: headlamp relay conversion/upgrade

Post by landon1 » Sat Dec 27, 2008 7:50 pm

well i went out and spent about 5 minutes and got it right....i was trying to do one side at a time, turn on the switch adn make sure they came on and everything...well, appearantly you can't do that...you have to replace all of the bulbs with LEDs, then turn on the switch....anyway, running lights, turn signals, hazards, brake lights all work...really no need to change the flasher can, as they are flashing fine (correct speed)

i may try to finish off the exterior lighting in LED but i'm not sure if the side markers will light up if they are LEDs since they don't require much power - it may think that the bulb is blown...we'll see i guess

But, headlight relay addition works great, as does switching taillamp 1157s to LEDs. :D

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Re: headlamp relay conversion/upgrade

Post by Serious Satellite » Sun Dec 28, 2008 1:14 pm

Just a site I found that addresses some issues stated here about led lighting. . . .

http://autolumination.com/gp.htm

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