Install Time: 1 hour (max) for novice, ~15 minutes if you have your dash apart already.
Cost: <$10
Discription: A "lights on" buzzer. Never leave your lights on when you leave your car again!
MKII's have the annoying key chime, so you don't forget your key in the ignition (despite the fact that you can't lock the driver's door without it anyway), but doesn't have any kind of headlight warning. Mine also shuts off the headlights when the ignition is off, but leaves the parking lights on, which is hard to notice in the daylight.
This may not look easy at first glance, but I have included a lot of explanation for novices and the electrically scared. There are lots of shortcuts which I have not included.
Difficulty: Easy

Parts needed:
1x Buzzer, rated at 14VDC or higher, ~90dB
--I used this one from MPJA.com, it is large, but the perfect tone/loudness.
--Radio Shack and All Electronics carry similar parts.
2x Crimp Terminals, type to fit to the buzzer
2x Power Taps (Vampire Clips)
~3' 16 guage, seperatable 2-conductor standed wire (or ~5' of single conductor, cut in half and mark one piece at both ends)

A) Getting Started:
1) Remove the entire driver's under-dash pannel (~4 #2 phillips trim screws to the kneebar, 1 panel retaining nut just above and left of the clutch petal.)
-- Optional: Remove the center console (two screws behind the ashtray, one under the shifter cover, slide back & disconnect lighter socket from behind) & kneebar (2 8mm Hex blots at each door frame). This takes a while, but will make access much easier.
2) Get Acccess to the wire bundle in the kick panel, near the door switch:
-- Remove the hood release lever (two #2/#3 phillips screws) from the kick panel, and pull back the carpet.
-- Optional: Loosen the driver's side kneebar bracket bolts (8mm Hex) from the doorframe. Pull the weather striping back from the area, and pull the plastic carpet retaining channel off the door frame.
3) Pull the headlight switch from the bezel using a small flathead screwdriver to carefully wedge it out from the bottom. Do not disconnect the harness.
4) Optional: Drop the fuse pannel for easier access. Remove the white clips by carefully pulling out on the tabs, rotate and pull. Then pull the panel away from the firewall and it should drop out safely.

B) Identifying the Negitive(-) Tap point:
Determine which OPTION you want to activate the buzzer from the diagrams below (#2 is reccomended). Either option works fine, but if you are particular, this is neccessary.

1) Remove the Driver's side door switch (torx/star screw), gently pull them out to avoid damaging the wires. There should be two leads.
-- Do not attempt to pull the leads from the switch, you will likely damage the switch.
2) Insert your key to the ignition.
3) Use a scrap wire (or screwdriver) to short one terminal to the chassis. Do not depress the switch.
a) If the overhead light comes on, this is Tap Point (1), used for option 1
b) If the door chime comes on, this is Tap Point (2), used for option 2
3) Repeat #3 on the other terminal to verify the points.
4) Note the wire color of the tap point you intend to use. This is your Negative Tap Point (1) or (2)
5) Slide the switch back into place while looking at the wire bundle near the hood popper mount. You should see the two wires sliding in -- this is where you will tap off the negative terminal.
6) Mark the matching wire, and reinstall the door switch. CAREFULLY pull the slack out of the kick pannel so you can tap it later.
7) Remove your key from the ignition, just to keep your sanity.

C) Identify the Positive(+) Tap point on the headlight switch:

1) Pull the harness out enough to get a tap on it
-- If you can't get it out far enough to get a DMM probe on it, remove the switch (temporarily), and fish the connector back down under the dash so you can work with it. Reinstall the switch until you're done.
2) Find the Parking Light (+) wire, terminal [TBD], wire color [TBD]
3) Use a DMM to verify this terminal is on when the switch is in the first on position (parking lights), and the key is out of the ignition.
4) Mark the wire, this is your positive(+) Tap Point (3)

D) Installation:

1) Prep your wire and crimp on your terminals to one end.
2) Note the orientation of the buzzer terminals (they are usually polarized), and mark the Negitive terminal and attach the wire. Mark the opposite end of the same negative wire.
-- Test the Buzzer by briefly touching it to the battery, neg(-) to neg(-), pos(+) to pos(+).
3) Seperate a length of the 2-conductor wire, and route the positive(+) lead to the headlight switch.
4) Use the tap to attach the positive(+) lead of your wire to the Positive(+) Tap Point (3).
-- Attach as far from the connector as possible. However, placement is not vital.
-- Do not reinstall the switch to the bezel yet
5) Route the negative(-) lead to the driver's kick pannel, and attach it to the Negative(-) Tap Point (1) or (2).
-- Attach as close as possible to the door switch from inside the car. Placement is not vital.
6) Test: With the key out of the ignition, turn the light switch to the first position (parking lights), and then:
a) Open the driver's door. You should hear the tone from the buzzer.
b) Close the driver's door. You should no longer hear the buzzer.
c) Open another door. ONLY if you chose OPTION 1, you should hear the buzzer.
-- Don't freak if it is annoyingly loud, it will be more muffled once installed in the dash.
7) Install the buzzer in the dash and secure all wiring.
-- Installation above the vent duct, under the driver's dash speaker works well.
-- For more volume, mounting it inside the duct should work.
-- For easier installation (if you skipped some of the disassembly), near the fuse pannel, facing down should still be audible.
8) Reinstall all the wiring, fuse pannel, switches, guage cluster bezel, carpet, weather seals, kneebar, and underdash panels exactly as they were removed (roughly in that order).

E) Only show off to other MKII's, most every other car ever made comes with this, standard.
F) Never have a dead battery again, at least not from leaving your f'n lights on.

KEY:

Option 1 is for buzzer on ANY door open

Option 2 is for buzzer ONLY on Driver's door open


Modified by stuston at 5:36 PM 10-23-2007

Middle Georgia EuroHoHs
Hellina, my MKII Jetta GL