high + low at same time with hid harness?

Printed From: the12volt.com
Forum Name: Lights, Neon, LEDs, HIDs
Forum Discription: Under Car Lighting, Strobe Lights, Fog Lights, Headlights, HIDs, DRL, Tail Lights, Brake Lights, Dashboard Lights, WigWag, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=114441
Printed Date: May 18, 2025 at 11:22 AM

Topic: high + low at same time with hid harness?

Posted By: californiaplaya
Subject: high + low at same time with hid harness?
Date Posted: June 14, 2009 at 5:25 AM

Just got a bi-xenon HID harness to use with a single HID kit. The HIDs are installed in an aftermarket projector capsule which uses a separate bulb for the highs and lows connected through a single harness. The HIDs are being used for the lows and I am going to keep halogen in the highs since I never really use them. The reason for getting the bi harness was to be able to keep the lows on when the highs are used. I don't use my highs much, but just in case I have to or hit the switch by accident, I don't want the HID ballast to repeatedly turn off and on.

I got it installed, but found out that the harness does not allow the lows to remain on when the highs are turned on. I will only be powering the lows through the HID harness, the highs will be powered through the stock harness. The harness is a bi-xenon hid harness. It has battery and ground, a 9007 male plug to get the signal from the stock wiring, three relays (two SPST and one SPDT - I think), and four connectors for the HID ballasts (two for each side).

When I turn the lights on, the lows through the harness work for the low side and when switched to high, only the highs work. What would I need to change on this harness so that the lows remain powered whether the switch is on low or high.

Thanks!!!

Replies:

Posted By: i am an idiot
Date Posted: June 14, 2009 at 7:12 AM

Since the HID trigger wire probably pulls very little current, you should be able to do this with one diode per side of the vehicle. I would still use at least a 3 amp diode. Radio Shack sells 3 amp and 6 amp diodes. Go pick some up and I will draw you a picture.

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Posted By: californiaplaya
Date Posted: June 14, 2009 at 12:38 PM

So just stick the diode between the low and high + on each side? Any other way to do this? I don't want to start cutting up this harness if I don't have to.

Posted By: californiaplaya
Date Posted: June 14, 2009 at 1:00 PM

Would adding a jumper wire from the high + in the stock harness to the low + in the HID harness work?

Posted By: i am an idiot
Date Posted: June 14, 2009 at 1:20 PM

A jumper would make both lights come on any time one of the lights were on.

Posted By: i am an idiot
Date Posted: June 14, 2009 at 1:52 PM

There is another way to do it, but since you need very little current to trigger the HID module, I think a relay will be wasted effort and money. I think the diode is the simplest and most cost effective manner. The relay will involve the same cutting of the harness.

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Posted By: californiaplaya
Date Posted: June 14, 2009 at 3:33 PM

I found another way using the stock wiring. Bridge a wire from the DRL diode to the headlamp switch. Don't understand why this works, but apparently it does. I'm going to try this first and if that doesn't work, I'll try your method. Thank you for the replies!

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