V
Switching taillight bulbs to LED
- Thread starter kdub_66VI
- Start date
JetTurbo
geezer
- Location
- South Florida, USA
- Car(s)
- 2018 GTi Autobahn 6M
The bulb type is 1156, but rysskii3 is correct.
While you can find an LED 1156 replacement, there are two concerns.
First an foremost, the LED will not stay lit.
The Vehicle Electrical System Controller J519 drives all exterior lighting.
Every brake light, reverse light, headlight, turn signal
has its own individual circuit on the controller.
The controller monitors current draw.
If anything draws too much power, or if
the LED bulb does not draw enough power,
and most LED replacments will draw too little,
the controller will kill the circuit as a form of protection.
The protections in the controller provide an
intelligent modern day self-healing 21st century replacement for the fuse.
So if you put an 1156 LED replacement in your tail light,
it will light up at first, then shut down within seconds
and a bulb out warning will appear on your instruments.
You can NOT disable the required exterior lighting circuit protections
with VAG-COM programming.
With stock coding, the controller will detect the problem shortly after key on
even before you turn any of the lights on (cold diagnosis).
While you can disable the power on check / cold diagnosis,
you can not disable active monitoring.
So disabling cold diagnosis simply delays the error until you turn the light on.
It is possible to fool the computer controller by adding a dummy load (resistor)
to consume additional power which will keep the sensor happy.
While fooling the controller makes some sense for simpler stuff like license lights,
not recommended for tail lights.
Second is the fact that an LED in an incandescent fixture
will perform poorly.
Even if the LED can produce more visible light,
light is coming from the wrong place, is the wrong shape,
and will not be properly distributed / focused
by the computer optimized reflectors and lenses in the fixture.
I have seen a couple of non-VW cars on the road where people have done this
and the lights were dim and very directional.
The proper way to get LEDs in your tail lights
is to purchase fixtures designed with the LEDs in place.
NateC
Passed Driver's Ed
- Location
- Webster Tx
I've recently been ticketed for my lenses being too dark. I purchased 4 LED lamps and am experimenting with some DIY quick fixes.
Although Jetturbo is correct about everything he said.
I still feel like there is another alternative to shelling out the 300-400 needed for a "simple" install setup.
Although Jetturbo is correct about everything he said.
I still feel like there is another alternative to shelling out the 300-400 needed for a "simple" install setup.