This DIY/FAQ is for the installation of an additional 12v Power Plug in the trunk/hatch of a GTI/Rabbit.
As always, any work you do on your car is at your own risk. Myself, and this website cannot be help accountable for anything that goes wrong while working on your car. Please undertake at your own risk.
extra 12v Plug, with wire leads (available from Radio Shack for under $10.)
Soldering Gun / Solder (if you'd like)
1) Follow my DIY for removal of the interior trim here: DIY/FAQ: Trunk / Hatch Interior Trim [Partial] Removal
2) As always, when working with automotive electrical, you'll want to check the current of what you're working on. The 12V plugs in the Mk5 are ignition switched, so if the car is off, you should be okay. You can remove the fuse and/or disconnect the battery if you'd like as well.
3) Cut the wire behind the harness. Strip the wires. Red+Black is hot, brown is the ground.
4) Splice in your new 12v Plug.
5) I used wire caps to splice the wires. I could have (maybe should have) soldered them together, but this seemed to work fine for my purposes. You can see here, the 12v plug I bought from Radio Shack is fused at 10a.
6) Here is the "somewhat" finished project:
7) Check your connections, to make sure everything was spliced correctly.
8) Put everything back together. There is ample room behind the trim for the additional plug. You'll notice I've also plugged in the accessory's 12v plug, and electrical taped the connections.
9) In case you're interested, here is what the extra plug is powering: