Daytime running lights

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chimera

506 posts

Ultimate Geek

#243587 19-Dec-2018 13:57

Hey,

I have some LED DRL's (daytime running lights) on my car, that came with it when I bought it. They basically come on with ignition on or car running, and automatically turn off when the headlights are turned on. The relay box for them looks like this, with RED, BLUE, YELLOW and BLACK wires going in.

No voltage to any wires with ignition off

With ignition on (or car running): Black = GND, Red = 12V, Blue = 0V, Yellow = 12V

With headlights on, BLUE wire changes to 12V (so assume its the wire to switch the relay off)

This all works fine.

However, I have put in a new grille and it comes with LED lights in it. I want to wire this up to do the same as above, however the driver than comes with it only has 3 wires, RED, WHITE and BLACK. By all intents and purposes, I assume BLACK is GND...

When testing these, connecting EITHER red or white to 12V, turns the LEDs on.

What I want to do, is wire it so that they turn on the same as the existing LEDs. I'm not really keen on using one relay and splicing the outputs from the first relay, I'd rather use the 2nd relay and wire it up to do the same job as the first one.

Question is - how do I wire this up to work so it turns off when the headlights come on? Or is this not possible with the current setup?

Cheers

1 | 2

2016 posts

Uber Geek

Trusted

#2147798 19-Dec-2018 14:16

Does the 12V on the Yellow wire disappear when the headlights are on?

Dingbatt

6756 posts

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#2147801 19-Dec-2018 14:20

You said using either red or white, what happens if you put 12v on both? One for power and one to trip the relay.
I have the 4 wire setup you described with your current setup on my aftermarket DRLs but the fourth wire was to dim rather than extinguish the DRLs so that isn't used as it's against the LTSA guidelines.

Chinese instructions, or none at all? 😁

“We’ve arranged a society based on science and technology, in which nobody understands anything about science technology. Carl Sagan 1996

chimera

506 posts

Ultimate Geek

#2147807 19-Dec-2018 14:31

Brunzy: Does the 12V on the Yellow wire disappear when the headlights are on?

No, it stays 12V

Dingbatt: You said using either red or white, what happens if you put 12v on both? One for power and one to trip the relay.
I have the 4 wire setup you described with your current setup on my aftermarket DRLs but the fourth wire was to dim rather than extinguish the DRLs so that isn't used as it's against the LTSA guidelines.

Using both it still lights up the LEDs.

Just the RED, it's very bright.

Just the WHITE, it's half brightness (so maybe white is dimming wire?)

Both RED and WHITE, it's half brightness

geocom

594 posts

Ultimate Geek

Subscriber

#2147820 19-Dec-2018 15:03

What is written in the fuse panel it may be possible to kill power to the lights without killing the relay logic from the computer(computer on one fuse lights on another)

Geoff E

chimera

506 posts

Ultimate Geek

#2147857 19-Dec-2018 15:15

geocom:
What is written in the fuse panel it may be possible to kill power to the lights without killing the relay logic from the computer(computer on one fuse lights on another)

Yes good idea, fuse box is close by so I can throw multi meter on and see which turns off when headlights are on and what’s on when headlights are off. I jjust traced the RED wire to old relay to the fuse box, using the fog lights.

Failing that I’m tempted to think this new “relay” is just an LED driver as opposed to an actual relay, as there does not appear to be a switching wire. I think if I got another relay, and placed it before this box and had the (blue) headlight wire switching the relay off when headlights are on then this would work.

Will have a look at current fuses...

chimera

506 posts

Ultimate Geek

#2147879 19-Dec-2018 15:36

Output on current DRLs is 5V, output on new grille DRLs is 12V. Think I might go super cheap and get a new relay.

neb

11294 posts

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#2148121 19-Dec-2018 22:36

chimera:
I have some LED DRL's (daytime running lights) on my car, that came with it when I bought it. [...]

However, I have put in a new grille and it comes with LED lights in it. I want to wire this up to do the same as above,

A note on DRLs, reports of their efficacy come primarily from regions like Scandinavia where you're driving in semi-gloom for a good chunk of the year. In countries with more normal daylight, there's no convincing evidence that they have any effect. So it may not be worth expending a lot of effort to set up additional lights.

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chimera

506 posts

Ultimate Geek

#2148123 19-Dec-2018 22:59

They came as part of the new grille, so for ~$10 for a relay, it’s not gonna break the bank. Irrelevant of functionality, they look good :-)

k1w1k1d

1526 posts

Uber Geek

#2148217 20-Dec-2018 09:55

Wiring for new three wire module to meet NZ rules;

Black = ground

Red = ignition

White = headlights.

Operation: The LED's will operate as bright DRL's with just the ignition on. Rather than going off when the headlights are on they will remain on dimly and become an extra set of front position/side lights.

You are only permitted one pair of DRL's, so will have to remove the other set.

MikeAqua

7785 posts

Uber Geek

#2148221 20-Dec-2018 10:02

I'm curious to know what the yellow wire in your older DRLs is for. The only thing I can think of is that you have separate power inputs for each light. That would mean double pole relay or two single pole relays.

Mike

chimera

506 posts

Ultimate Geek

#2148241 20-Dec-2018 10:25

k1w1k1d:

Wiring for new three wire module to meet NZ rules;

Black = ground

Red = ignition

White = headlights.

Operation: The LED's will operate as bright DRL's with just the ignition on. Rather than going off when the headlights are on they will remain on dimly and become an extra set of front position/side lights.

You are only permitted one pair of DRL's, so will have to remove the other set.

"You can fit up to two daytime running lamps to your vehicle. If your vehicle already has two daytime running lamps as original equipment, you can’t fit a second pair. On some vehicles, daytime running lamps operate as a function of the main beam headlamp."

"Daytime running lamps must be wired so that they automatically switch off when either the dipped or main beam headlamps are turned on"

https://www.nzta.govt.nz/resources/get-your-lights-right/get-your-lights-right/#day

EDIT: By "two DRL's" I don't know if they mean 2 sets, or 2 meaning one left and one right. Due to ambiguity, I have a valid argument to running "2 x DRL's" however.

dolsen

1476 posts

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#2148250 20-Dec-2018 10:36

chimera:

"You can fit up to two daytime running lamps to your vehicle. If your vehicle already has two daytime running lamps as original equipment, you can’t fit a second pair. On some vehicles, daytime running lamps operate as a function of the main beam headlamp."

"Daytime running lamps must be wired so that they automatically switch off when either the dipped or main beam headlamps are turned on"

https://www.nzta.govt.nz/resources/get-your-lights-right/get-your-lights-right/#day

EDIT: By "two DRL's" I don't know if they mean 2 sets, or 2 meaning one left and one right. Due to ambiguity, I have a valid argument to running "2 x DRL's" however.

"If your vehicle already has two daytime running lamps as original equipment, you can’t fit a second pair."

Seems pretty clear to me.