EDL questions

[Ti Kan]

EDL uses the ABS wheel sensors to determine the speeds of each wheel.
When under power and one wheel suddenly spins faster than the one
on the other side (indicating a loss of traction), the EDL system
will apply brakes to the spinning wheel.  This, in addition to stopping
the wheelspin, also has the effect of transferring drive torque
to the opposite side through the differential, hence allowing that
side (which has traction) to get you going.

Note that the name "EDL" is a misnomer of sorts because it doesn't
actually "lock" any differential.  It achieves a somewhat similar effect
by applying the brakes on the side that lost traction.  It only "engages"
when such a condition is detected.

EDL works in the front axles between the front wheels, as well as
in the rear axle between the rear wheels.

The driveline clicking sound could very well be the EDL doing its thing
as it uses the ABS brake modulator.

Summer tires are no good in the snow.  Definitely get them changed
if you're going to drive in snow regularly.

-Ti
2003 A4 1.8T multitronic
2001 S4 biturbo 6-sp
1984 5000S turbo
1980 4000 2.0 5-sp
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Rokas Reipa writes:
> Hey everyone. Having owned two FWD audis, I am ready to tackle this winter
> with my 1995.5 S6, which has quattro IV with EDL(no diff locker button). I
> am curious to understand exactly how it works. I understand the theory but
> am interested more in how I would know when it's working on this particular
> car. When does it engage and does it engage/disengage periodically or does
> it engage, lock the rear/front diff and then stay engaged until 30mph or so?
> I'm curious to test out if it works at all. It finally snowed here last
> night and I had a chance to try the car out. Every once in a while, there is
> a faint repetitive clicking coming from the driveline when applying
> throttle; would this be edl? Noticed quite a bit of oversteer when applying
> throttle on curves; I guess this can be attributed to the crappy summer
> tires which will be changed soon. Any and all comments are welcome. Thanks!