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Huh?

Why relay your headlights? well - if you have aftermarket light housings, or are running higher wattage bulbs, then you are exceeding the capacity of the factory wiring in your car. Relaying the headlights makes the path the power has to take much much shorter. In stock form, the power goes from the car battery back to the fuse panel. Then it goes through a relay that turns them off when the key is turned. Then it goes through the fuses, then up to the headlight switch. It goes right through that switch (ever feel that switch get warm?) Then, it goes back into the wiring harness and back up to the front of the car to connect to the headlights. All of this wiring is just the right gauge for stock bulbs (VW does not want to spend even an extra penny per car - this is mass production). All of this wiring is 15-25+ years old.

Long path.

So - relaying does this... The power goes from the battery to the fuse, then a few inches to you're relay box. Then it goes to the headlight. MUCH shorter. The advantage here is that since you can use new wiring, you can make it a larger gauge than the stock wires are. And you can happily run 110W bulbs all day long and not fry wires.

Parts!

Alright, For this, you need to go down to the auto parts store and find some really good crimpers. Don't get the kind for insulated terminals, those are crap. Get the kind with the notch that will make sure that you connections are TIGHT.

Here's a list of parts you may need:
Wire: Get at least 14 Gauge - I used 10 (Overkill)
Project box - Radio shack. holds the relays
4 Relays, Bosch 30A - Get these from www.partsexpress.com
4 Relay sockets - Also parts express
Terminals, plugs and H4 connector - all in the auto parts store.
Inline Fuses - ATO is better because they are easy to find.

Soldering iron, shrink wrap 3:1 with adhesive

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You can buy some of the parts online. Here's some that I've found... You can also find most of these things at a Pep Boys, or Advance Autoparts or the like.
	Bosch 30A Automotive Relay			30A Automotive Relay
	Relay Socket			2 place Relay socket (this is rare)
	Bosch Relay socket - no wiring pigtails. This is very good for making your wires go directly from the relays to the headlight sockets with no splicing of wires.
	H4 Headlight Socket I've found that advance has a good one with pigtails attached if you would rather splice wires then crimp.

Instructions:
Alright, look at that diagram. The way I have it set up, the stock wiring stays the same. When I got my lights, they came with these cheesy H4656 to H4 connectors (which were wrong, BTW), I used one to plug into the low connector on the driver side. I put the project box there in front of the battery, it's close to the power and there's nothing there anyway.

Fuses:
Don't ignore the fuse! It may not seem like a far distance to go, but a short is REALLY bad. Ever seen a car battery explode? It isn't pretty.
How a relay works:
there are 5 pins on the bottom of a relay. A relay is a remote switch that turns something on when it gets a voltage on the trigger pins (86 and 85). It doesn't matter which is ground and which goes to the old low beam. the other terminals are where the new wiring comes in. Connect the battery (through a fuse) to pin 30. When the relay is triggered, that will go on through to pin 87, which you attach to the H4 bulb. 87a is where the power would go when the relay is not triggered, so don't connect that to anything.

Wiring Diagram (In semi-normal people format)
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First Version here is the 4 relay - for Redundancy!

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But - When it comes down to it - 2 relays work just fine! I suggest using 40A relays!

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