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Thread: HID headlight relay.

  1. #1
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    Default HID headlight relay.

    Hey...so, having my HID's in, i realized it would not be good to anti-up the fuse to double its stock rating for them to work. (one works with a 7.5 and other with a 15). I've decided to purchase a relay system, in hopes that I can keep my stock fuses and protect the wiring in my car. What does everybody think of this? - I really don't think i'd have the skill/paitence to make my own harness.
    http://www.xenondepot.com/product.php?product_id=50


    Simply connects to a ground , a postive (I'll probly wire it to the postive batt terminal in the engine), and then to the 9006 connectors on the ballast. Would this let me keep the stock 7.5 amp fuses and still run the HID's?

    www.KaRealtySF.com
    Build Date: 05-1995 /Engine: m50tu /Automatic Transmission /ABS /NO ASC /Open Differential /EAT Chip

  2. #2
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    Quote Originally Posted by liquidtiger720
    Hey...so, having my HID's in, i realized it would not be good to anti-up the fuse to double its stock rating for them to work. (one works with a 7.5 and other with a 15). I've decided to purchase a relay system, in hopes that I can keep my stock fuses and protect the wiring in my car. What does everybody think of this? - I really don't think i'd have the skill/paitence to make my own harness.
    http://www.xenondepot.com/product.php?product_id=50


    Simply connects to a ground , a postive (I'll probly wire it to the postive batt terminal in the engine), and then to the 9006 connectors on the ballast. Would this let me keep the stock 7.5 amp fuses and still run the HID's?

    Kind of sort of...

    You should just put a 15 AMP fuse in! Think about it, look at the wires leading to other units that have 15 AMP fuses... same gauge.... I am running dual 15's as well.

    By running the relay, you have to worry about the relay working. They tend to not be so reliable in the engine bay w/ heat/wet. And additionally, you will have to fuse the relay line ANYWAY, so you'll be putting a 30AM in-line fuse on the +12v anyway... why not do a 15A each side?

    6 one way, a half-dozen the other.

  3. #3
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    so, you think'd id just be okay using a 15amp fuse in place of the stock 7.5?

    Would save me lots of money, hehe.

    Thanks...btw.

    I'll take a look at the wiring tommorow.

    It's odd that one ballast works fine with the 7.5 amp, and the other wants 15 amps!
    Last edited by liquidtiger720; 09-25-2005 at 10:13 PM.

    www.KaRealtySF.com
    Build Date: 05-1995 /Engine: m50tu /Automatic Transmission /ABS /NO ASC /Open Differential /EAT Chip

  4. #4
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    Quote Originally Posted by liquidtiger720
    so, you think'd id just be okay using a 15amp fuse in place of the stock 7.5?

    Would save me lots of money, hehe.

    Thanks...btw.

    I'll take a look at the wiring tommorow.

    It's odd that one ballast works fine with the 7.5 amp, and the other wants 15 amps!

    Yes you can use a 15A fuse. Its not that odd... figure how accurate a fuse is... it could be +- 20% i'd figure... so 20% of 7.5.... i dunno, almost 10A? Maybe its pulling 8A or 9A and the one fuse is a little bit more lenient. Either way, I've got 15As in my box for my philips HIDs and they're working great, never blew a 15A yet.

  5. #5
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    a relay set up would allow the use of large gauge low resistance wire and let those ballasts draw just what they need........the other side of the argument.You could prolly mount the relay in a spare spot in the fuse box......
    Gone but not forgotten

  6. #6
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    Just put in 15A fuse. I had it running for 4 years now... zero problem. Beside, if you put in a relay system, you will run into same problem with rockyfeller... low beam warning every single time you turn it on. As opposed to the rest of us, who gets low beam warning only when light is off... but easily fixed with a simple relay device to fool the computer the bulb is good.

    I tried to help Rocky with his problem but man! it is tougher to fix.

  7. #7
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    Quote Originally Posted by Tiger
    Just put in 15A fuse. I had it running for 4 years now... zero problem. Beside, if you put in a relay system, you will run into same problem with rockyfeller... low beam warning every single time you turn it on. As opposed to the rest of us, who gets low beam warning only when light is off... but easily fixed with a simple relay device to fool the computer the bulb is good.

    I tried to help Rocky with his problem but man! it is tougher to fix.

    would you like to elaborate on the relay to fool the computer that the light is good!?!??!

    www.KaRealtySF.com
    Build Date: 05-1995 /Engine: m50tu /Automatic Transmission /ABS /NO ASC /Open Differential /EAT Chip

  8. #8
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    i'm running a relay harness, since nov 2002. no problems.

    but as tiger stated, you will get the lbf as soon as you turn on your headlights. doesn't bug me any more, i could care less.

    even with this set up, i'm running 15a fuses anyway.

  9. #9
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    HID doesn't have continuity like a regular bulb... so to 'fool' the computer... you have to show a continuity... like 1 to 4 ohm and 1 watt resistor. Using the relay, you wire it so when headlight is off, the circuit is complete to the resistor... when headlight is on... it disconnect the resistor. If you don't disconnect the resistor when headlight is on... the resistor will burn up.

    The relay assembly must have its own fuse to protect your headlight wire harness.

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