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How to: 2007/2008 Full Time Daytime Running Lights (FT DRL)

I have been rading this over and over, can some one answer a question for me.  I only want my fogs to come on with DRL but I dont want FTDRL.  Can this be done and would i use the same fog diode size and shich way should stripe be running on diode.

Thanks
 
You can do that.  Just put the diode between the Fog Relay and the DRL.  The stripe on the diode would be closest to the DRL.  That allows the DRL to turn on the Fogs, but not vice versa.
 
You'll have to check in your underhood fuse box.  I know that some of the numbering is different between the model years, but you can see the pic in the first post above.
 
Well, this was one of my first mods along with the amber DRL today.  Great information and pics...thanks.  Though when I finished installing the diode to the right fuse (hehe....first time I accidentally installed to fuse 29....horn fuse....ouch :E:), I noticed it was very,very hot.  Then I looked at the new amber bulbs (26watts each) and thought about it (26w\12v=2.16A)...slightly over 2 amps each.  Decided to break out my fluke multimeter and get in line on the diode to measure the current.  As expected from the calculation, ~4.34 amps.  Probably would be OK with the 3amp diode, but removed it anyway.  Going to grab a relay today and tie it in similar on the control (parallel the coil on the light relay), but pull a hot from elsewhere and feed it to fuse 31 via the new relays normally open contact.  Anyway, just thought I would mention going the relay route and to say thanks again for the pics and info......it got me off my butt to start some mods!  Looking at HID next.  :B:

-=J
 
Well, got around to installing the relay today and added the always on fog light mod too.  Everything worked great.  Tied a radio shack automotive relay in parallel with the light relay and then grabbed a hot (to turn on DRL) from an item not in use (which happen to be the running board accessory light).  Ran the other side of the normally open contact to fuse 31 and now all time running lights.  I might add that no diode is needed for the DRL when using a relay the way I have it tied (power from an item not in use).  Also tied the neg of the coil to the fog light coil (via a diode - since this relay can be energized via a different source) so the fogs would be all the time too. 

Again, thanks for all the pics and info on this thread.....it was a huge help figuring out how I wanted to run mine!  Pics to follow.

-=J

Edit - Forgot to add terminal numbers:  (for 08')
Fog light relay is term #85 which needs negative to energize
Low beam light relay term #86 is the negative (used to energize) and #85 is positive (always present)
Did not see any numbers for the running board light where I pulled a positive (but it was the term closest to you standing on the drivers side)





 
I did this mod a few days ago and this is my results...only at night or with the truck in the garage, I have park lights, drl's, fog lights, and headlight low beams, all on at the same time. When the truck is out in the day light with this mod, all I have on is the drl's. Is this what the mod is supposed to do?  ???
 
This mod is to keep your DRLs on when your headlights are on.  That's it.  Normally, the DRLs would shut off when the headlights are on, ie at night. 

The automatic headlights/fogs/high/low beams is a separate issue.  You probably have your headlight switch on Auto - this is the light sensor determines when to turn on your headlights.  That's why at night or in the garage (or in rainy weather) your headlights come on.  Normal mode for the AV is that the BCM turns off the DRLs when the headlights come on.  This mod uses the headlight relay to turn back on the DRLs.
 
After a couple of days, the diode has burned up for the FT drl's. This is what I used...1N4004 rectifier diode 1 amp 400v.
 
old skool said:
After a couple of days, the resistor has burned up for the FT drl's. This is what I used...1N4004 rectifier diode 1 amp 400v.
Click to expand...

Check my posts above.  I measured more than 4amps running to my DRLs and listed a link to a 6amp diode that would work.

edit.....Well, in my head I posted the link...oh well...here it is!  http://www.parts-express.com/pe/showdetl.cfm?Partnumber=6A-1KV

-=J
 
Drunk_J said:
Check my posts above.  I measured more than 4amps running to my DRLs and listed a link to a 6amp diode that would work.

edit.....Well, in my head I posted the link...oh well...here it is!  http://www.parts-express.com/pe/showdetl.cfm?Partnumber=6A-1KV

-=J
Click to expand...

Thanks, I'll give it a try.
 
Drunk_J said:
Check my posts above.  I measured more than 4amps running to my DRLs and listed a link to a 6amp diode that would work.

edit.....Well, in my head I posted the link...oh well...here it is!  http://www.parts-express.com/pe/showdetl.cfm?Partnumber=6A-1KV

-=J
Click to expand...

Using the bigger diode, it gets extremely hot...it this safe?
 
old skool said:
Using the bigger diode, it gets extremely hot...it this safe?
Click to expand...

Well, at 6amp it is at least rated above the current you are pulling and way safer than the 1amp diode you had in there....hehe.  But if you'll notice from my post with the pics, I went with a relay instead of a diode.

 
Well, if this diode burns up, I guess I'll go with the relay. What is the part number for the Radio Shack relay? Can I get one like it at AutoZone? Looks like the relay has 3 prongs...is this right. Can you give more precise pin outs of the wiring?..hard to tell where each wire is routed to, and what wires you have soldered at the relay...sorry, I'm no electrician.  ???
 
Drunk J
It appears in the picture that you connected to the fog relay on the upper right corner. I like to know what I am connecting to before I do it so I took voltage readings on that corner and I read a positive voltage to the chassy ground. If you are controlling the ground wire to the coil then this would be wrong (according to the reading I took) The positive side is always at the coil. I am making a diagram for those who don't know anything electrical.
 
LornesAV said:
Drunk J
It appears in the picture that you connected to the fog relay on the upper right corner. I like to know what I am connecting to before I do it so I took voltage readings on that corner and I read a positive voltage to the chassy ground. If you are controlling the ground wire to the coil then this would be wrong (according to the reading I took) The positive side is always at the coil. I am making a diagram for those who don't know anything electrical.
Click to expand...

To be perfectly honest, I don't even remember which relay is what now.  Got tired of the mod and pulled it off a little while back.  Not sure if maybe it is hard to tell in the pic or not which term it really is hooked to....it could just be tucked under that corner but goes all the way across (I listed terminal numbers you could check on the relay).  But the way it was hooked up worked perfectly which only could have occured had I given it a ground (otherwise it would be a direct short and blow the diode).  Are you measuring your voltage with the relay partially plugged in, if so, you are reading the voltage through the coil (not trying to be insulting with that question, simply offering another possibility).

-=J
 
Fully cladded 03' Z17
I know this has been done to death but I'm going to ask anyway, sorry! I have my ambers and want to hook up "Angel eyes" and grill led tape so that they all are full time(not the fog lights tho) but don't want to splice into any wires, just go directly to the box. All that can be are led externals already so I've already fixed the "fast flash" issue. Anyone have any suggestions? 
 
OK, so I did this mod between last night and this morning and here's a couple issues / questions...

1. The diodes seem like they are getting really hot...is this normal?  Measured with a IR temp gauge and reading over 200 degrees.

2. Using the bottom left of the HL relay didn't work for the fog light mod.  It doesn't get voltage unless the lights are off.  I went with top left like the DRLs and went to bottom left of the fog light relay when looking at it at the same orientation as the HL relay.

3. I noticed the fog lights come on all the time with the headlights and this isn't what I really wanted.  I actually want to still be able to switch them on and off, but don't want them to go off on their own when the brights come on.  Is there a different way to make it work this way?
 
If you don't want the fog lights, remove the smaller diode - the one from bottom left in just the red and black wire.  That's the one that turns on the Fog Lights when the low beams are on.  The big diode is the one that runs the DRLs (red and blue wire). 

I can't speak to temperature.  As I said in the first post, I'm not sure if it is the right sized diode, it's just one that works.

And btw, I'm at over 3yrs running with this mod and everything is running fine!
 
Is there a different place I can connect the fogs?  Like can I run them normal kind of like the DRLs, but when the hi beams kick on it gives them power so they stay on?

Anyone know?
 
Well, if you looking for Fogs off on low, but fogs on on high, then you just need to connect that diode to the high beam relay instead of the low beam relay.  You'll have to check your fuse box for exact location and do the same kind of testing I did with a multimeter.
 
Thanks, I'll do some digging and see if I can figure it out.  I actually want control of the fogs at the switch on the dash and I want them on with the low beams and hi beams.  Factory default makes them kick off when you go to hi beams.  So my thought was I probably need to to the diode set up tied to the high beams so when they are trying to kick off, the hi beam voltage overrides and essentially turns them back on like the DRL mod does.
 
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