Thread: DRL ideal

OK, I had some time to dig into this more yesterday. My goal is to be able to gain more control over my lights, but not nec cut out DRL all together.

One obvious answer is the use the signal for the dash lights (can grab this easily). The only potential problem is that this drops below 12v if you use the dimmer. I have never used the dimmer knob other than to see that it worked and when testing yesterday so this wouldn't be that big of a deal.

I did some searching and found that the sensor on the dash gives a ground signal rather than 12v. The wire to the BCM is light green with a black stripe and is in position 15. When using it as a ground and connecting it to my multi meter, I get full 12v (actually higher) when it gets dark and the headlights come on automatically. This ranges and changes as the sensor sees light. I saw as low as 6v yesterday, but it wasn't very bright. I imagine I could get close to 0 on a sunny day. I tried a test using this for the ground on a relay and the relay would not switch. This was a standard 50amp relay I had laying around. I am trying to figure out how get a relay that will switch (close) as the ground allows a full 12v, but open back up as this drops down to 10-11 volts. That sort of electrical thing is not something I am used to dealing with. Any insight would be appreciated. As I continue to work on this, I will post my findings.

I tested my voltage for pulsation at the headlights when DRL's were active and saw a constant full voltage no matter what test light, multimeter, etc that I used. I expected to see pulsation as many have experienced, but could not duplicate it.

Originally Posted by LeadfootCJ7

OK, I had some time to dig into this more yesterday. My goal is to be able to gain more control over my lights, but not nec cut out DRL all together.

One obvious answer is the use the signal for the dash lights (can grab this easily). The only potential problem is that this drops below 12v if you use the dimmer. I have never used the dimmer knob other than to see that it worked and when testing yesterday so this wouldn't be that big of a deal.

I did some searching and found that the sensor on the dash gives a ground signal rather than 12v. The wire to the BCM is light green with a black stripe and is in position 15. When using it as a ground and connecting it to my multi meter, I get full 12v (actually higher) when it gets dark and the headlights come on automatically. This ranges and changes as the sensor sees light. I saw as low as 6v yesterday, but it wasn't very bright. I imagine I could get close to 0 on a sunny day. I tried a test using this for the ground on a relay and the relay would not switch. This was a standard 50amp relay I had laying around. I am trying to figure out how get a relay that will switch (close) as the ground allows a full 12v, but open back up as this drops down to 10-11 volts. That sort of electrical thing is not something I am used to dealing with. Any insight would be appreciated. As I continue to work on this, I will post my findings.

I tested my voltage for pulsation at the headlights when DRL's were active and saw a constant full voltage no matter what test light, multimeter, etc that I used. I expected to see pulsation as many have experienced, but could not duplicate it.

At this point what are you trying to accomplish? IF you tape over your light sensor youll have no DRL. And you just switch your headlights on manually.

Originally Posted by 91parkave

At this point what are you trying to accomplish? IF you tape over your light sensor youll have no DRL. And you just switch your headlights on manually.

I have gone back and forth, but currently I am settled on this: I want the fog lights and LEDs (or LED Halos) on. I am doing a HID projector retro soon and don't want them on all the time. Then, when it is truly dark have the projectors come on with the fog lights etc. The side benefit is the fog lights being on with the headlights, etc without always having to switch them on.