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As I posted in this thread, and testing the wires inside the headlight housing, I did not find that the light blue wire was energized with headlamps on. It was only energized while the headlamps were off and the shifter was not in park. If the DRL was energized with headlamps on my diode cluster would not be working as posted in that thread. My LEDs would be full brightness all the time, which they are not. My system depends on the DRL circuit being dead with headlights on.

If there is a mechanical or other type of switch inside the headlamp housing, it must be prior to the light blue wire inside that runs to the DRL.
 

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Decided to take the plunge and give it a shot. Worse I would do is burn out a driver FET in the BCM. I've done this repair on many vehicles so not concerned about it.

Haven't measured the actual draw on the DRL LEDs, but figured they can't be more than 30W. Picked up two 3A 50V Diodes from radio shack. "Back probed" the headlight harness for a quick test. Works like a champ. Pin 1 (top left when looking at the female end) is the 12V+ for the halogen headlight. Pin 2 (to the right of pin 1) is the 12V+ for the DRL LED. Cathode goes to Pin 2 (DRL LED) so current will only flow from halogen to led, not the other way around.

Radioshack part# 276-1141. Will come up with a more elegant solution another day, this was just a test.

Sorry for the long video, too lazy to edit it/trim it.

https://www.youtube.com/watch?v=D2LgQapITT4

I put a flash light over the ambient light sensor to trick it into daylight mode. The vehicle is in neutral with the e-brake applied since the DRLs dont come on in park. Only tried it on the driver's side for a "proof of concept."

I'll measure the amperage draw on the DRL LED tomorrow to make sure those diodes are sufficient. I'll also come up with a better wiring solution. I'm trying to think of a non-permanent way since this vehicle is leased. Even though I hate them, I may use some quick splices so I don't have to cut/solder the wires. Even though I'm confident I could leave it that way and nobody would ever know.
 

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Discussion Starter #23
YES YES YES YES YES!!!! That is exactly what I'm looking for! Thank you!

I was down in the garage last night checking things out again and I had come to a similar conclusion but I didn't have a diode handy to test with.

I am going to stop by Radio Shack today and try this tonight. If it works on mine as it does on yours, I'll put together a more permanent solution. I bought mine so I can do whatever, but I hate cutting the factory wiring unless I have to so I may use quick splices and wrap it up nicely.
 

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20140722_123248.jpg 20140722_123240.jpg 20140722_114655.jpg 20140722_115345.jpg I failed to come up with a non permanent solutuon I like, and im not recommending this but im willing to take the risk. I ground down the diode leads and back probed both connectors with the diode. Normally id be concerned with voltage drop and excess heat... but these are low current LEDs we're talking about here so I dont see an issue. I heat shrinked the diodes just incase of it contacting something metal and grounding out.

Now I just need some Sylvania ZXE bulbs to bring the color temperature up.
 

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Decided to take the plunge and give it a shot. Worse I would do is burn out a driver FET in the BCM. I've done this repair on many vehicles so not concerned about it.

Haven't measured the actual draw on the DRL LEDs, but figured they can't be more than 30W. Picked up two 3A 50V Diodes from radio shack. "Back probed" the headlight harness for a quick test. Works like a champ. Pin 1 (top left when looking at the female end) is the 12V+ for the halogen headlight. Pin 2 (to the right of pin 1) is the 12V+ for the DRL LED. Cathode goes to Pin 2 (DRL LED) so current will only flow from halogen to led, not the other way around.

Radioshack part# 276-1141. Will come up with a more elegant solution another day, this was just a test.

Sorry for the long video, too lazy to edit it/trim it.

https://www.youtube.com/watch?v=D2LgQapITT4

I put a flash light over the ambient light sensor to trick it into daylight mode. The vehicle is in neutral with the e-brake applied since the DRLs dont come on in park. Only tried it on the driver's side for a "proof of concept."

I'll measure the amperage draw on the DRL LED tomorrow to make sure those diodes are sufficient. I'll also come up with a better wiring solution. I'm trying to think of a non-permanent way since this vehicle is leased. Even though I hate them, I may use some quick splices so I don't have to cut/solder the wires. Even though I'm confident I could leave it that way and nobody would ever know.
That is some solid reverse-engineering right there!:cool:

May have to rethink how I perma-disabled my DRL by just moving Pin#2 to an unused pins on both headlamp connectors!:p

Maybe leaving Pin#2 DRL voltage from BCM moved to any of the unused pins 6-8 on that connector so it isn't being used then just shorting pins 1&2 together internally inside the headlamp so that the DRLs are ONLY on when the headlights are turned on then off when the headlamps are turned off...hmmmmm
 

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That the DRL's are burning with the headlight is normal here in Netherlands.
So it should be possible


I'm sure it's programmable in the BCM, however I'm not willing to pay the dealer $125+, and they probably wouldn't even do it for a leased vehicle.

In all honesty I should probably also protect the BCM by putting a diode on Pin 2 supply, with cathode pointing towards the headlight, however if the gate to the FET is off, it really shouldn't matter.

What headlight bulbs do you have in yours? They must be a higher color temperature than the LEDs to make the LEDs look "orangish." I'm assuming the LEDs are in the 5500K range? My stock halogens are probably 3000K. Only alternative I know of is Sylvania ZXE "Xenons" which just has a light tinting to the bulbs.
 

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That is some solid reverse-engineering right there!:cool:

May have to rethink how I perma-disabled my DRL by just moving Pin#2 to an unused pins on both headlamp connectors!:p

Maybe leaving Pin#2 DRL voltage from BCM moved to any of the unused pins 6-8 on that connector so it isn't being used then just shorting pins 1&2 together internally inside the headlamp so that the DRLs are ONLY on when the headlights are turned on then off when the headlamps are turned off...hmmmmm
After studying the wiring diagrams, that should be 100% OK. All voltage regulation for the LEDs seem to be internal to the headlight assembly. It's just a 12V power source switched by a FET in the Body Control Module.

The reason for the diode is so when the BCM commands ONLY the DRL LEDs on, it's not trying to power the halogen headlights. That would easily over load the FET(s) driving the LEDs and probably cook them. If you are going to dis-connect pin 2 then there is no risk of a higher amperage draw on that circuit.
 

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I have 4300k Xenon in the headlights. Here they are just turned on and warming up to their normal color.

Here some other pictures where you can see the xenon matches the DRL very good:


 

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Discussion Starter #30 (Edited)
I went by Radio Shack today and got the same diodes that poor_red_neck got. Very simple installation. Just bent the leads of the diodes, oriented the cathode properly and forced them into the back of the pins. I put a drop of glue on it and taped it up (didn't have shrink wrap). Works perfectly!

Now, my next project is to put a strip of LED rope of some sort inside the bottom of the turning signal assembly where it looks like there should be one. :)

Here is the finished product from tonight.

https://www.dropbox.com/s/b0uxpc1aoi2jh8t/Dale _IMG_0477.JPG
https://www.dropbox.com/s/uwd1bvdp3izdr3m/Dale _IMG_0475.JPG
https://www.dropbox.com/s/a77o98i0le39r8t/Dale _IMG_0476.JPG
 

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I had previously modified the DRLs to stay off by just moving pin#2(DRL PWM voltage from BCM) on both X110 & X120 (Drivers/Passenger Side headlamp connectors) to unused pin#8 on those connectors as detailed above...





22 - 18 AWG Red Tap Splice Wire Connectors

Instead of having to use a diode, I sourced the above tap splice connectors from Home Depot. 3M makes a similar splice connector...





Spliced the Yellow(Headlight PWM Voltage) & Grey(DRL PWM Voltage) internally on both Driver/Passenger headlamps so now the DRLs are ONLY on when the headlights are turned on then off when headlights are off. Since the splice was performed inside the headlamp assy behind the cap, no need to follow-up by weatherproofing this connection...





Having the DRLs on when the HID bulbs are turned on throws a lot more light out. You can see the weatherized/oversized 80A relay with green LED I'm having to use in order to drive the HID ballasts in the pic above due to the fact the PWM headlamp voltage is not fused after leaving the K9 Body Control Module. Much like the diode mod, If I ever tire of having the DRLs being on, I can just pull off the splice connector to return to normal wiring!;)


BTW: This is NOT recommended for those folks living in areas where DRL use is mandatory!
 

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My general Volt warranty just expired so I decided it is time to finally take ownership ;)

Used the same 50V, 3A rated rectifier diodes from Radio Shack. Measured about 850 mA draw via the diode to the DRL light and about 12.1V at the headlight connector (the DRLs are 10W apparently). The diode gets warm, may have to pull out the IR thermometer to see how warm. Used a hammer to flatten the diode leads so that they can fit through the wire rubber sleeves in the connector. Since I don't have a fancy wide shrink wrap I used a 3M Super 33 vinyl electrical tape rated for outdoor use and at up to 105C to isolate the diode leads and to keep it snug to the wiring harness. We'll see how well it works tonight.

I am concerned that the DRLs will blind the oncoming traffic as the light is rather bright and not as focused as the projection headlights. On many occasions I have already been flashed by oncoming traffic. They thought I had my high beams on even though I was just using the low beams. I still have the factory HIR bulbs.

A couple of gripes, whoever placed the air intake filter box so close to the right-hand headlight assembly needs to have their head examined. It is almost impossible to unplug the headlight. The engine coolant overflow line and the high voltage orange wire harness feeding the charger are right there too, so be careful if you mess around in that area.

Update: The DRLs really help with the peripheral vision. Because of the different light color it is easy to see what is primarily illuminated by the headlights and what is illuminated by the DRLs. The road signs lit up and I could see them much better both from afar and while they were passing by. This mod seems easy enough and rather useful now that the nights are longer and we drive more in the dark.
 

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I did somms DRL/headlight mod method over the weekend. Since I had previously disconnected the DRLs by following the Youtube video of moving a pin in the connecting plug, all I had to do was go to the local auto parts store, purchase a couple tap splice wire connectors, and install them.

The driver’s side was a piece of cake, fifteen minutes and done. The passenger side was, of course, more difficult. The air cleaner is so close that is very hard to get tools or even fingers inside the headlight housing. Beyond that there was noticeably less slack in the housing wires on the passenger side, so trying to get the tap positioned properly was not easy.

I took off the air cleaner lid to get some more clearance. That helped a bit, but not enough. Deciding something had to give, I tried prying the air cleaner base to see if I could gain a half inch of space. and the whole base promptly popped free. Turns out it is held on by three friction fit rubber grommets to some metal framework. Now with all the room I needed, five minutes later the passenger side tap was in and ten minutes later everything was buttoned up.

Like others, I had been concerned with the lack of illumination at the front corners of the car. It made it a lot harder to see signs, curbs, random kamikaze wildlife, etc. I’m hoping that this mod will solve that problem. I like the look of the lights and there is certainly a lot of illumination. I can see how oncoming traffic might mistake the lights for high beam since there are clearly four lights visible now. But if it works in the Netherlands, it should be able to work here as well.

cheers!
 

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We need pictures.
 

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We need pictures.
OK, pictures as requested.

Close-up of headlight and DRL.



From the front – looks pretty bright.



Further away from an angle.



Fifty yards out.



I like the looks of the DRLs, I just didn’t like them on during the day. So this is a good way to put them to use. If you consider straight ahead is 12 o’clock, I find the DRLs add a fair amount of close-up illumination at the 11 and 1 o’clock positions and a bit at the 10 and 2 o’clock positions. The light color is not the same. The DRLs are blue and the stock headlights are yellow.

I was bit worried that the combination of the lights would be too bright for oncoming drivers for the reason that headlights are focused to a specific point to help the driver see what’s in front of the vehicle while DRLs, on the other hand, are just light sources that make the vehicle visible to other drivers during the day, and as such might create glare at night.

But as you see from the fifty yard out picture, there doesn’t appear to be significant glare for oncoming drivers. What the pictures don’t show though, is that as you approach the car, you can clearly see four lights. This may tend to make other drivers think there is a pair of high beam headlights on, like some of the cars from years ago, that had separate high and low beam headlamps.

I'll be going for a long night time drive on a two lane highway this weekend. It'll be a good test to see how the new setup works.

Cheers!
 

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I can't understand why anyone would want to defeat the Daytime Running Lights.
They are there for safety.
Any study of this subject in any country conclusively shows DRL's save lives.

SAFETY.

I can understand wanting the DRL on along with the standard headlights.
More lights in the front.

More SAFETY.
 

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I didn't see any mods that allow the DRLs to stay on and force the headlights off. Maybe I will shine a flashlight at the light sensor :)
 
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