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DRL for 98 Honda Civic

Printed From: the12volt.com
Forum Name: Relays
Forum Discription: Relay Diagrams, SPDT Relays, SPST Relays, DPDT Relays, Latching Relays, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=31783
Printed Date: August 25, 2025 at 10:52 AM


Topic: DRL for 98 Honda Civic

Posted By: silverctr
Subject: DRL for 98 Honda Civic
Date Posted: May 07, 2004 at 7:49 PM

FYI: I did do a search and found a few helpful threads. :D I want to use the high beams as DRL, but have them shut off when I turn the headlights on. Here's what I got so far since I'm relay wiring challenged:

87-high beam+ with a resistor in line to dim light output

86-swtiched 12v

85-ground

30-switched 12v

Two questions about this setup: Will this even work? Will this shut off when I turn the headlights on? Any help is appreciated here.




Replies:

Posted By: boomer_106
Date Posted: May 09, 2004 at 12:51 PM

The way you have it No its not gonna work. I cant see how the headlights would shut if off.   When the relay is at rest 30 and 87a have continuity. When the coil is energized 30 and 87 have continuity. Study the relay page here at this site. The way I have it figured since the 98 civic has positive headlights (Red wire at the headlight switch use your meter to verify first) you would connect the Red headlight wire to pin 85. Pin 86 would go to ground. 87a would go to your lights. 30 would go to an ignition wire. This is important. You must make sure the ignition wire is just that, an ignition only wire. You dont want it to have voltage in the acc position or if you were to park and turn your key backwards to listen to the radio your lights would be on. This would allow your DRL to come on with the ignition. Since the relay would be at rest 12 volts would pass through 87a til the coil is energized allowing your lights to come on. Once the coil is energized the connection at 87a and 30 is broken and 30 and 87 have continuity therefore leave 87 blank. The coil would become energized by turning on the headlights because you would be using the positive of the headlight wire on pin 85 as mentioned and pin 86 would provide the ground part.

In summary 85 to headlight wire at the headlight switch.   86 to ground 30 ign switched 12 volts 87a to headlight wire. 

Let me know how this works for you.





Posted By: silverctr
Date Posted: May 10, 2004 at 3:06 PM
Thanks boomer. After reading your post I realized I need a SPDT relay. I have a relay that came with my air horns that I thought I could use, but it must be a SPST relay because it doesn't have 87a. Your explanation answered the other questions I had too. Thanks again.

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Posted By: boomer_106
Date Posted: May 10, 2004 at 8:52 PM
Your welcome come on back and let us know how it worked out in case someone else wants to do the same.




Posted By: silverctr
Date Posted: May 11, 2004 at 7:15 PM

boomer_106 wrote:

Your welcome come on back and let us know how it worked out in case someone else wants to do the same.

I probably won't get to it until this weekend, but if it works, I'll be doing a DIY thread for www.civichatchback.com. If it's cool, I'll post the DIY here as well.



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Posted By: boomer_106
Date Posted: May 12, 2004 at 12:47 AM
That would be cool





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