DRL and low beams swapped

KyleB

Member
Joined
Jan 17, 2015
Location
Des Moines IA
TDI
09 Jetta
I've got what I think is a weird one for you.
I've had my 09 Jetta TDI for a few months now. It took me a bit to figure this one out. I mean, how often do you look at your car with the lights off then on? The daytime running lights and the low beam lights have been switched. That is to say, any time the ignition is on, my low beams are on, and when I turn on my lights with the switch, the DRLs turn on. All the other lights seem to work with the switch as you'd expect.
Is this a possible mod with VCDS?. Is there an easy way to swap a couple wires to achieve this effect?. It's this likely an error someone made in the past, or has anyone heard of doing this on purpose?
Ultimately, I'd like to undo it. But that means figuring out how it was most likely done in the first place. Thought I'd start by picking your brains.
 

JSWTDI09

Top Post Dawg
Joined
Jan 31, 2009
Location
Las Vegas, Nevada
TDI
2009 JSW TDI (gone but not forgotten)
An '09 is a MK5 chassis. Unless your lights have been replaced, the low beams and the DRLs are the exact same bulbs. Mk5s use the low beam bulbs at a reduced brightness as DRLs. Mk6 cars have a separate bulb for DRLs. Which bulbs are you referring to as your DRLs? Try this: park (stop) facing a building or wall at night. Start the car, DRLs should come on. Lift the parking brake handle and they should go off. Now turn on the headlights the light on the wall in front of you should get a little brighter (headlights on at full power). How do your lights work when you do this?

Have Fun!

Don
 

KyleB

Member
Joined
Jan 17, 2015
Location
Des Moines IA
TDI
09 Jetta
Here are photos of what I'm talking about:
DRL, ignition switch is ON, headlights switch OFF:


Low Beam, ignition switch ON, Headlights switch ON:


And finally for completeness
High Beam, ignition switch ON, headlights switch on, turn signal stalk pushed forward:


Now as you can see, turning on the low beams turns on a small lamp that I had assumed was supposed to be the DRL. I can see no perceptible difference in the intensity of the main bulb when switching the headlight switch on and off. Are you saying this is the normal condition? If so, what is that small lamp supposed to be for? Seems strange to me.
 

meerschm

Top Post Dawg
Joined
Apr 18, 2009
Location
Fairfax county VA
TDI
2009 Jetta wagon DSG 08/08 205k buyback 1/8/18; replaced with 2017 Golf Wagon 4mo 1.8l CXBB
That is the way mine works, and has since I drove it off the lot in sept 2008.

and if/when that little marker lamp goes out, you just pull the little socket straight

(no twist, as compared with removal of the bright or dim headlights which need a little under a quarter twist to remove)
 
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KyleB

Member
Joined
Jan 17, 2015
Location
Des Moines IA
TDI
09 Jetta
Ok i'll accept this is normal. So, what's the point of that small lamp? Is there ever a condition where it is the only lamp on? The engineers must have had a good reason to put it in, and as far as I can tell it's only on when the low beams are on anyway.
Also, will my MFD tell me if other lamps burn out?
 

meerschm

Top Post Dawg
Joined
Apr 18, 2009
Location
Fairfax county VA
TDI
2009 Jetta wagon DSG 08/08 205k buyback 1/8/18; replaced with 2017 Golf Wagon 4mo 1.8l CXBB
It is really of more use with a different light switch than we get here.

in some cities in europe, you cannot drive with the headlights on in the city, and these little lights mark where you are and let folks see you.

we used to have parking lights, and some cars still do.

my mfd has let me know the left dimmed light was out, (headlight)

pretty nice feature.

( I would have figured it out pretty soon anyway, but nice to have)
 

brkdrvr

Well-known member
Joined
Mar 2, 2013
Location
Milton, DE
TDI
2011 JSW TDI 6spd manual 140K, 2012 JSW TDI A/T 50K, 2014 JSW TDI A/T 40K, Ross Tech VCDS-MOBILE
My daughters 09 SportWagen does the exact same thing. She swears the city lights used to be on with light switch off and when switch was turned on the city lights went off and the low beams came on. /i am wondering if getting a european switch would resolve this and if the city light is sufficient as a DRL or if it would be if converted to a LED? Any ideas appreciated.
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Completely normal behaviour.

City light is NOT sufficient to be used as DRL. Don't waste you money on more powerful bulbs (e.g. W10W halogens) or LEDs. I have gone through all of this with my previous Mk5 and every "solution" was nothing but diappointment.

Here are possible solutions:
-Use as it is (use VCDS to choose between Scandinavian or North Americal DRL mode, whichever you like most);
-Move DRLs to fog lights if the car has got them;
-Get a Mk6 which has got real/seaparate DRL bulbs.
 
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