added inner lights wiring suggestion (VAG-COM required)
I can't either... I think I will go without the rear fog lighting to start and eventually wire it when I figure out how else I want them wired. Because, I want all 4 "Oo (v) oO" to light red (inside light housings as well) which will require additional wiring like the rear fog. But I want them to look good, so it may take some time to research first..
I have a suggestion on the wiring.
I have been considering this for a while - some background ... I have added a rear fog and messed around in this area's wiring and programming. For those who might not be aware, as delivered in all markets including US, the left and right backup lights are independently wired. The left side backup light may be redefined to new function with a pin swap and VAG-COM, allowing it to operate independently of the right side backup light.
I am saving to add LEDs to the inner reflectors. LED tails are already set up to accept them, the flat spots in the reflectors line up with euro LED tails outer fixture LED ring (removed from its fixture). Jetta or Golf outer LED rings will line up with this Golf inner fixture.
As part of adding the LEDs, I will disassemble the inner fixtures. I will remove the red rear fog lens while it is disassembled, regaining two backup lights.
I will share my wiring plan with you - most of it will apply.
Such a set up provides an interesting simpler wiring option that provides VAG-COM programming the illumination level of just these new inner LEDs.
Step 1, follow the DIY for rear fog enable. This process will manipulate a little used option of the rear fog circuit.
Step 2, electrically disconnect rear fog bulb (now converted backup light) from factory harness.
Connect left-side backup light bulb to the right side backup light so both share the same right side backup light circuit. (with the dual color LEDs, I will also jumper the yellow circuit into the backup lights).
BTW This wiring is much easier if you pull the hatch inner cover. (it is a pain to pop free)
Step 3, connect the now available rear fog circuit to all your new inner red bulbs.
Beyond the simple factory changes for rear fog, there are no new wires to run outside the ones under the rear hatch cover. This method keeps the new lights isolated from the safety critical outer lights.
Step 5, Last, but no least, get a VAG-COM and change the following Vehicle Electrical System Controller J519 (aka Central Electrical Controller) setting, try 10% to start, adjust to match (Dec:
10)
Byte 10, use the decimal entry field
(I have tested and confirmed the parking light backup function with a normal rear fog.)
Now, every time your outer rear parking lights illuminate, so will your new inner lights. Normal head light switch control, will even work with the stock switch.
New lights are on their own isolated circuit where they can't easily interfere with your important lights if they get wet and short, etc. :wink:
And then if you should install and wire a euro switch, pulling it to the rear fog position will jump them to 100% and you have dual rear fogs. :eyebulge: while retaiining dual back up lights :wink: all with normal factory controls :thumbsup:
PS - The LEDs I plan to use will satisfy the lamp out sensors. If your new inner bulbs do not consume enough to satisfy the lamp out sensor on the fog circuit, a resistor may need to be added. I have done this as well when I experimented with LED bulbs in backup light fixtures (waste of time). With the hatch cover off, there are good safe places to mount a sensor bypass.
switch - resistor - splice – the resistor is on the other side of the metal inner panel, just the rivets holding it in place are visible
