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  1. #1

    Default 99 high and low beams on at the same time

    Hi Everyone,

    I have been searching for the past couple of hours, and doing google searches but am coming up with nothing for a '99 silverado. Does anyone have information on how to wire the headlights so the low beams stay on when you switch to high beams? I have hid kits installed on both, but, they take a few seconds to fire up. At 88fps that's around 300ft before you can see, scary.

    I'll keep searching but if you know of a mod, I'd appreciate if you could help.

    Thanks,

    Jim

  2. #2
    Master Mechanic
    KyleZ71's Avatar
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    Default

    I know jc whittney use to sell some type of overide fuse i believe.. My father had it on his 96 tahoe. but then again he did not have hid lights
    Objects in mirror are losing

    2003 Chevy Silverado Z71, 5.3L, K&N 57 series, 2.5'' Flowmaster Super 10 series dual exhaust , Corvette Servo, McNew Automotive Dyno tune, SS gauge cluster, Extang Trifecta Tonneau, Pacesetter shorty headers, Goodmark cowl hood, Sony Xplod speakers, Kenwood DDX-470 exhaust tips, 16" Ultra Badlands polished wheels, Pirelli Scorpion ATR .

  3. #3

    Default

    There's a diode mod listed in the How-to Guides section of these forums (at this link: http://www.gmtruckclub.com/forum/sho...#axzz1wxSyfzbq). It may or may not work with 99's; you'd have to inspect your under hood fuse box and compare to the fuse and relay layout shown for the mod to be sure.

    Surreal

  4. #4
    Sr. Mechanic ChevyHD's Avatar
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    The diode won't work on his body style because he doesn't have two relays for high and low. You need to take the ground lead from you low beam and ground it to your truck.
    Last edited by ChevyHD; 06-05-2012 at 05:03 PM.
    Adam
    2004.5 CCSB Duramax
    Max Effort Tuning by Idaho Rob - Goerend Transmission - PCV ReRoute - EGR Blocked - Plugged Resonator - 5" Diamond Eye Turbo Back - Tie Rod Sleeves - All On Mod - Edge Insight CTS - Recon Taillights, Cab Lights, & 3rd Brake Light

  5. #5

    Default

    Quote Originally Posted by ChevyHD View Post
    The diode won't work on his body style because he doesn't have two relays for high and low. You need to take the ground lead from you low beam and ground it to your truck.
    Thanks for the clarification. I wasnt' sure what he had in the fuse box. Was worth a shot...

  6. #6
    Sr. Mechanic ChevyHD's Avatar
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    Quote Originally Posted by SurrealOne View Post
    Thanks for the clarification. I wasnt' sure what he had in the fuse box. Was worth a shot...
    Yup, I was hoping the diode would work as well for my truck but its rather simple to do it. Helps out a ton.

  7. #7

    Default

    Hi Everyone,

    I found this on another forum. The '99 only has one relay to control the high/low beams and I think it does it through the BCM.

    So, here are the instructions. I just did this and it works perfectly. Took 10 minutes, tops.

    and I quote:
    "
    1) Open hood
    2) Remove brace from firewall to Driver's side fender.
    3) remove top of Circuit panel
    4) unhook the snaps from the passenger and drivers side of the cover...look hard they are there!
    5) Roll entire circuit board over towards the passenger side.
    6) Locate the Grey connector...there is only one.
    7) at location D3 (3rd down 4th to the right) is a light gauge yellow wire. It is the only yellow wire in this row.
    8) Tap this wire and ground it to the Light ground on the firewall. Follow the lead from the Hood mounted light, and you will find it ...just to the left (YOUR OTHER LEFT!!!) of the Master Cylinder.
    9) Put your stuff back together...you are done...arent you glad you kept that cover?
    Enjoy your new quad headlights!

    I cut and pasted this from another forum but have done this and it works great. There is another way to do it using a relay but this is alot easier and since your working on the power side and not the dround you don't need a fuse. The lights themselves are fused on the power side of the circuit."

  8. #8
    Sr. Mechanic ChevyHD's Avatar
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    That's doing the same as what I said, just more complicated lol.

  9. #9

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    Quote Originally Posted by ChevyHD View Post
    That's doing the same as what I said, just more complicated lol.
    LOL, yep. I guess it just spells it out... good thing is it works.

  10. #10
    Sr. Mechanic ChevyHD's Avatar
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    Yup, I'm glad you accomplished your goal!! lol its my favorite mod easily!

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