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DRL Resistor: Location and Bypassing

17K views 20 replies 10 participants last post by  VAGguy  
#1 · (Edited)
I read that the DRL resistor could be easily bypassed. This is handy if you install HID headlights, want to retain DRLs, but don't want to bother with a separate relay harness wired to the battery. Of course, simply unplugging this will also disable DRLs, so it's also an alternative to removing relay 173.

The DRL resistor is beneath the passenger side lower A-pillar panel. Pry off the cover, remove one Phillips screw, and you can remove the cover. It's held on at the top by a clip.

Beneath this you will see a number of connectors. The bright pink one at the bottom is the one you want (in my 2003 B5.5):

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After unplugging it, you will need to jumper across the two leads open leads if you want full voltage for your HID DRLs. I used a simple "bayonette" crimp-on terminal. You can get these at any auto parts store, including WalMart. It fits perfectly!

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Button everything back up and you're set. Once you have installed the jumper, you will now have full current available to your HID lights as DRLs. As an alternative, if you simply leave this connector unplugged you have disabled your DRLs.
 
#2 ·
Very cool. :thumbup:

Please nobody bash this. This is great if you want to retain the DRL function with DRLs.

Good job.
 
#4 ·
Not sure how this would invalidate a Euroswitch. My Euroswitch doesn't affect the DRLs at all. I ultimately want to do the Audi-style DRL mod, but simply haven't yet mustered the time to delve into that. I'm not sure how to get the lower cover off of my B5.5 to expose all the needed wiring.

Even so, because I have 3000K VVME HIDs in my OE fogs, I'll still have to bypass this resistor as I have recently found thet the VVME ballasts do not do well through the DRL resistor (I suspect their starting current is higher). In contrast, my McCullouch ballasts seem to do fine with it.

As for the e-brake lever switch: you're right. If that's broken, your HID ballasts will not be happy when you try to start the car.
 
#5 ·
Biggest advantages to getting a euroswitch [and after disabling DRLs] are:

* being able to run only dash lighting, parking lights, side markers and tails
* being able to run fogs in addition to above

DRLs are, just that, for daytime use. They do not improve your vision during the day. They are simply a mandate to propose the fact that visibility of *your car* to *other drivers* is improved during daytime. So, they run at lower power to serve the need.

If you run DRLs, you lost your ability to run *just* fogs/dash/markers/tails - why euroswitch?

What is an audi style DRL?
 
#6 ·
What is an Audi style DRL?
These were written up by a past member, Bonthran. The "Audi style DRLs" use the side marker lights and fogs as DRLs instead of the the headlights. Here's the link:
http://www.passatworld.com/forums/showthread.php?t=106495.

If you want DRLs, this mod illuminates the corners and fogs in the "off" position. In the first ("park") position you get dash lighting, corners, sides, and tails; fogs are off but you can select them independently. In the second position, you get full lighting. It's a neat mod.

Frankly, I think it should have been done this way from the outset. At the very least, DRLs should be disabled in the park position.
 
#7 · (Edited)
As an additional bit of info, with the Euroswitch you can get the DRLs to behave such that:

Switch position "OFF"
DRLs ONLY,

Switch position "PARK"
corners, tails, dash, city lights (if applicable), fogs on first pull, rear fog (if installed) on second pull, NO DRLs,

Switch position "ON"
Everything.

You can accomplish this by disconnecting tab "B" on the Euroswitch. You can do this by three possible routes:

1) Bending down or breaking off tab "B"
2) Taping over tab "B"
3) Removing the wire in the plug that connects with tab "B."

I chose against option 1) because I dislike irreversible mods. I didn't use option 2) because the contacts will, after time, squeeze through the electrical tape and make contact again. So, I used option 3). I put heat shrink tubing over the end of the wire, and marked it such that if I ever want to undo this mod, I know where it goes.

Removing these connectors from the plug seems to be a bit different. I didn't investigate this very much, but I did the usual drill: stuck paper clips in either side of the connector (there are spaces on either side to allow this). But then, I also had to lift up a small plastic tab on the outside of the plug. I used another paper clip to do that.

Now my DRLs behave as I wish: in the park position, they are off, allowing me independent fogs. In addition, because I've jumpered across the DRL resistor it will not longer cause problems limiting current to the HID ballasts.

I've decided against the Audi style DRLs for my B5.5 because my corner lights don't behave like my wife's B5. In hers, the PARK position illuminates the same bulbs that serve as turn signals. I assume that this is through the "running" filament. In my B5.5, the running filament in the turn signal is never used. In fact, has no contact! So, while it would certainly work for a B5, I'm not sure I'd get what I'm after on my B5.5.
 
#8 ·
I've decided against the Audi style DRLs for my B5.5 because my corner lights don't behave like my wife's B5. In hers, the PARK position illuminates the same bulbs that serve as turn signals. I assume that this is through the "running" filament. In my B5.5, the running filament in the turn signal is never used. In fact, has no contact! So, while it would certainly work for a B5, I'm not sure I'd get what I'm after on my B5.5.
I took the + wire from my bumper marker and ran it to the blinker bulb you speak of. Since the B5.5 takes a dual filament bulb, I figured I should use it!!!

I drilled a hole in the blinker holder, soldered a wire to the other tab, sealed with silicon, then taped power from the bumper markers. They are now blinkers and parking lights.

As for the Audi style DRL, I have everything ready to do the change over, but I just broke my hand, so I'm pretty F*ing useless
 
#9 ·
That's a neat mod. WHen I looked in my socket for the turn signal bulb, I didn't see a contact for the second (lower power) filament. I'm curious about how you managed to get the new contact to provide enough pressure to make good, reliable contact. I'd like to these lights to be on when I have my parking lights on, too.

Bummer on your hand! I hope it's not too serious and heals quickly and well.
 
#12 ·
I think this only works when using a Euroswitch in the "Park" (center) position. When off, these marker lights don't illuminate, only DRLs if enabled. Thee marker lights do illuminate in the Park and On positions of the Euroswitch.
 
#17 ·
My only excuse is that I wanted DRLs, but did NOT want headlights on in the Euroswitch "park" position. This way, when I turn on parking lights that's all I get, unless I choose to turn on the fogs. Then, in the "park" position, I can have fogs, but no headlights. It's a control thing...
 
#21 ·