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Discussion Starter #1
Hi all, newb here. I've always been more of a street bike guy (where electronics are simpler...).

Car: 2008 GTI
Problem: The low lights both stopped working simultaneously (I wish I knew the exact moment). The only thing I noticed between perfect function and no function was that my fog light switch was turned on for the first time to my knowledge in between. I didn't know what it was, but I pushed the switch back in and now I know it was the fog light switch. So it sounds almost like a short/blown fuse, but I would've expected more to go awry if it was that. Now the DRLs/low beams do not work under any circumstances. The downside for me is that the prev. owner had HIDs installed (poorly, in this guy's opinion, e.g. loosely resting modules, barrel clamps for wires etc.), and I have yet to find a free copy of the lighting wiring to figure out how they're wired in. I COULD completely disassemble the front of the car to see everything, but that is annoying as hell and I hate doing physical work for something that could easily be diagnosed based on analyzing the circumstances. Especially since I think the problem isn't that far downstream, given both lights went out simultaneously.

I tested some things and here's what I found: High beams work, but only if the ignition is on AND the low beam switch is on, which is how it's supposed to work. The dash lights also still come on. The significance is it tells me the low beam switch still functions. All other lights work how they should on the car (except I never tested fog lights before so I ignored their impact here--they don't work, btw). So it sounds like something between the switch and where the wiring is split to the two lights? I would guess the relay itself. I checked the fuses and they're good. I checked the wiring near the headlights and don't see any loose parts.

Actually, the A/C stopped blowing cold just recently too, so they could be related. When the A/C is "on", there is no compressor running anymore.

Could someone please post a pic of the relay or other helpful info regarding fuses or maybe a even a wiring diagram for this? Even which fuse(s) are involved would be a great help since the manual is wrong. I've heard the one closest to the windshield relates to lights, but like I said, it looks fine.

Please don't suggest trying new components to see if it works--I refuse to buy parts and install before knowing what the problem is. These things can be easily tested for free if I know a bit about the system, hence me trying to learn about the system here :)

Thanks!
 

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If you had a multi meter you could test the circuit at the headlights, before and after the ballasts.
 

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Discussion Starter #3
I have to get one. That was my thought, but I suspect it's further upstream since both lights went out simultaneously. Do you know what comes before the ballasts in the circuit? I would have to take apart the whole front of the car just to see and no guarantee I'd have a good look from there.
 

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Lighting circuit has separate fuses for the lows and highs, for each side. Aside from that, it's the switch.
 

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If the aftermarket HID where installed with a relay kit, I bet it's the fuse in the relay harness.

It should be about 6" from the positive lead on the battery.

If it was a cheap relay harness then the fuse holder and fuse probably started to melt.

From my Note 2
 

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I'm Watching You
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Wait this is a mk5 so it should have factory HID. If there is a aftermarket system installed then it's probably for the fog lights.

From my Note 2
 

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Discussion Starter #7
Really? The boxes seem to be wired directly to the low beams. The computer has always barked about both "dipped beams not working" upon startup even though they did, which led me to believe the seller about them being an after market addition. Now its barking actually makes sense since the lights don't work...
 
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