Sorry to re-hash an old topic, however I tried to make my own DRL bypass today and have one issue. When the ignition is turned on, but not started, it works great and does what it is supposed to do. However if my lights are not turned on before I start the car, they will not turn on. When I crank the car over, there is a quick flicker from the headlights, like they try to fire up, even though they should not be on. I used a 4.7 capacitor rated at 300V. I also used a diode, as stated a few pages back. Wondering if anyone has an idea why this happens. Also if the headlights are on and I shut them off, they won't turn back on....when car is on, when car is off, everything works perfect. Hope someone can help me out. Thanks.

 

Never mind, figured it out. The store gave me 4.7k resistors instead of 47k....now it is working like a champ.

 

Wondering if anyone with know-how on this can explain something for me...

I'm planning on trying option 3 but there's one thing that I don't understand... The instructions say I need an extra 9006 cable, but what for? As far as I can tell you don't need it, you can just cut the only female plug off the relay harness (the one that attaches to the driver's side stock harness), and work with the 4 wires that result (the other end leads to the remote turn on lead)... My harness has two male connectors coming from the remote turn on lead can go to each ballast unmodified... Maybe I'm mistaken? Do I need two of everything so I can install two MOSFETs?

Actually my understanding is that you only need to cut the ground wire of the plug, you can leave the power wire intact and only strip the rubber to attach the 50 kohm capacitor... Is this correct?

Sorry for reviving an old topic (again) but as far as I can tell this is the only method to keep HIDs off in daytime... Please help

 

Yes MikeOMG you are correct. You only need to cut the female, however it is easier to cut both +ve and -ve and then solder all the stuff on. Did mine a few weeks ago and it worked great, just make sure you get the right resistors.

 

So I went ahead and tried soldering it up but I couldn't get it working and I can't see why... its probably wrong i just tried to follow the instructions but i dont know electronics and this is my only attempt at soldering... it blew a fuse when i plugged it in... booo can someone check what i did wrong? the instructions and diagram were kindof confusing, I wouldn't be surprised if it's something simple

Maybe the wrong resistors or capacitor..???

 

Hard to tell from your image, but it seems fine. I assume you are using resistors to get up to the right resistance? I used a diode, so means I could use 2 x 47k instead. Here is an image I used for doing mine and helped me a lot. Best of luck and hope it works for you. Also, fuse should of not blown since I think the lights would of just flickered if not working right. Maybe you hooked up the relay wrong.

 

Sorry about the huge image, first time posting one. Looked at your wiring again, seems you capacitor is backwards, seems you have the negative connected to the source, I think it should be the other way around.

 

Sorry, wrong again.....i'm really messing this up. All resistors should be soldered to the Gate. Then 50 to female, and 28 gets soldered to the Source. So you have to unsolder your positive, then solder the 50 and 28 to the gate......now solder end of 50 resistor to the +ve, not the end of the mosfet.......now solder the 28 to the source along with the ground wire. Just follow the image I posted and you will be fine.

 

Sweet man, 5 minute fix and it works perfect! Wish I had that diagram the first time, lol!

 

I was skeptical about capacitor rating so I simulated the circuit when DRL is ON in Simulink Power Systems

Here is the circuit:


And here is the voltage output versus time at the MOSFET input. For the IRF510 MOSFET the threshold voltage is 4V, so here we can see that when DRL is ON, it holds steady at about 2.57V and therefore the HIDs would stay off. Once the headlights are switched on you would expect double that voltage ~5.14V and this would trigger the MOSFET to open the gate.
Note: I simulated using an input voltage of 14.3V cause that's what my civic runs at.

 

I just ran another simulation with the mosfet semi-conductor and hid load.

For all of you running option #3 with flickering problems. The resistances need to be reversed. The 28k first and then the 50k connecting to the ground.

The reason behind this is that the MOSFET also restrict's the current passing through the HID ballast as a function of the MOSFET S input voltage. After running the numbers, you won't get enough current going through the HIDs unless the input voltage of S is about 8.04V. ~[(28000/78000)*14.3V]. With the resistors the other way, it's only 5.14V. So you end up with something like 20% of the current it needs thus causing flickering.

My final conclusion is that the circuit is clever but probably not a good idea unless you understand what you're doing. (ie. Electrical tech or engineer).

 

Any body still have a picture of the Modified Circuit used for Option #3? It's not showing up in Post 79 anymore.

 

I made some modifications to the #3 circuit which allows the fog lights to run as DRLs. Using a circuit simulator applet, I've found that the circuit is most reliable using 2 diodes. This remains true with the DRL fog light circuit working or not. I've also been considering using an emergency bypass circuit that allows me to run the headlights in the event that something fails in the main circuit. The diagram is showing 50k resistors, but works fine with 47k ones as well. If anyone has suggestions to improve this circuit, let me know.

 

If you are willing to spend the extra money and save some time and headache,
I think this http://www.ebay.com/itm/140587017196...WAX:IT&vxp=mtr would be a good option, I think I am going to give it a shot!

 

I'm back! So many posts on this thread! Who knew I'd come back in a couple years and see people using and even selling my design on eBay...hope the profits are going to charity, as I definitely haven't received any royalties...lol

I sold my Lancer back in 2009, so wasn't coming to the forums anymore. Just picked up a 2009 GTS last week, so came back here to refresh my memory on how I fixed the DRL/HID issue

I uploaded 2 images below. First is the schematic I used to simulate the design. Second is a more simplified/labelled schematic for those wishing to build one.

It took me 20 minutes to build and I can verify it works wonderfully on the 09 GTS.