Vaccum hose for door locks: Where is it

[Helge Wunderlich]

First of all, thanks to all who replied, including those who replied
on email.

On Tue, 26 Mar 2002 19:56:00 -0500, Huw Powell wrote:

>under the back seat, under the passenger floor carpet, under the
>covering in the kick area in front of the passenger door would be good
>places.

I took a look under the back seat. It seems the hoses run under the
carpet, and removing the carpet does not seem like a simple job. The
hose at passenger's side, however, is nice and easy to access.

>Pick one where you can do a nice job of running the hose over the
>drivers door.

Running the hose across under the dash was actually much easier than I
had thought.

>I presume you are adding a pneumatic actuator to the drivers mechanism,
>and have some "spare" recycled Audi green plastic hose and connectors
>handy?  or there already an actutor there, but with no hose running to
>it?  I can never remember.

See details below.

>Anyway, sounds liek a cool project, please report in detail when you're
>done!

OK, here are the details:

First problem: Driver's door does not have a vacuum actuator, only an
electric switch.

I had a spare (from a junkyard) passenger's side actuator. First, I
planned to replace the existing switch with this actuator, but it
turned out to be possible to combine parts from the two to make an
actuator that also contains a switch. Now I can operate all door locks
with the key too, just as before. The modification was, however more
trouble than it was worth, since the key will only be used for
emergencies anyway. It does make one minor difference: When attempting
to lock the doors while the driver's door is open, the locks will open
again immediately (since the switch stays in the "up" position). With
only the actuator, the other doors will stay locked, while the
driver's will stay open, even after closing the door.

I bought some braided fuel hose (mostly because that's what they had
in stock) of the right size, and routed it from the driver's door,
under the dash across to the passenger's door and tapped into the
vacuum hose there using a "T"-connector. I considered cheap PVC hose,
but abandoned that, because I think it might break after a while.

Next problem: Finding suitable electronics.

Since this car is not suitable for remote central locks as it is, it
is not listed in any application charts. I chose one that was for some
Mercedes and some Audi models. The important thing is to pick one that
is for vacuum operated locks, since you need it to "hold" for a few
seconds to allow the pump the necessary time to activate the locks.
Mine is labeled "Speedy", and is produced by an Italian company called
"Autosonik" (don't tell anyone I have Italian electronics in my Audi
:-). They have a web page, but it mentions nothing of this product.

The electronics device's connections turned out to be two SPDT relays
that activate every other time the button is pressed. Once this
information was at hand (took some time, the documentation did not
contain any technical details), creating the proper connections was
fairly simple. If I hadn't needed to maintain the function of the key,
the connections would have been super simple.

While working on the project, I came up with a different solution that
is a bit more expensive, but probably much easier: Buy an electric
actuator, and put it into the driver's door (keeping the existing
switch). Finding electronics to operate the electric actuator is easy,
and there is no need to fiddle with any vacuum hose. This actuator
activates the lock as well as the switch, which in turn activates the
rest of the locks through the stock central locking system.

--
Helge Wunderlich