Only Drivers door locks
 

When locking by turning key in door or by fob the only knob that goes down is the drivers. All doors will open. The pump is good.

If it were a door lock actuator why would 3 doors fail all at once?

If it were a leak how would all doors open?

Checked fuses and CLP connections.

Really stumped!

I have a similar issue: the front passenger door locks only sometimes. In your case, my guess is that there's a leak at the pump end of the system: from the pump one branch goes to the trunk and the other goes to the doors; the branch to the doors is further branched, and the driver door is the first one. I think this setup is to enable two-step locking (which I've activated due to my problem): a very brief action of the pump unlocks only the trunk and the driver door.

I can see why only drivers door works.
 

It's on a separate air hose circuit.

I see there are smoke testing machines that shops use.
Short of taking off 3 sets of door trim to look for leaks what other ways do I have to find this leak?

http://www.v-techuk.com/english/prod...ster/index.asp

I guess it's one of the connectors. If you find a solution, please take some pictures and share them. Personally I don't know how to access those connectors. Around left wheel well?

The Driver's door and the fuel door release are on one circuit. The other doors and the trunk are on another. You need to move more air to operate the 3 door/trunk circuit than you do for the driver's door/fuel filler door.


The driver's door lock mechanism gets cycled far more than the others. Over time the door mechanisms get sticky. You could try spraying a bunch of WD40 into the other door lock mechanisms on the side of each door, and operating the doors/ locks to work it in. Some swear by this others say don't use WD40 because it displaces the proper lubricant from the locks. Well, if they aren't working, you don't really have much to loose.

Also, the air pump (located in the passenger side of the trunk tucked away behind the trim panels over the wheel arch in a block of shock absorbing foam) dies. It is made of a graphite material and eventually the three blades spinning in the eccentric pump chamber disintegrate. There's a guy who sells replacement pumps for $65. I think I just saw a link referencing him in the quattroworld d2 forum.

Along this line, wouldn't continual spray of silicone grease work as well?

All really good advice.

I have already rebuilt the pump in the past year. Its working strong.

I left out one odd thing about current function:

The pump OPENS the 3 doors (non driver) but wont CLOSE them!
So that cicuit can pump but not vacuum.

however the divers closes so vacuum works.

I'm going to see if I can plug off the branch of the 3 door circuits that goes to the trunk latch and see if I can at least isolate the leak from that circuit.

praying its on the trunk side and not on the 3 door side. :)

Christmas just came early for my D2!

The connector to the trunk circuit was hard to get off (squeeze with needle nose and wiggle out with small flat head screwdriver)

but when I plug the trunk circuit with my finger the 3 doors close.

Off to run down the trunk leak!

Soo happy not be having to run down leak on 3 door circuit.

Merry Christmas!

Found leak.

Tear in rubber boot on "Rear trunk lid operating valve"
4A0862153B

#4 in Diagram

Got a 97 A6, unfortunately the smaller connection on the pump operates the fuel flap only. The large connection operates doors and trunk. There is a valve inside the unit that opens for pressure from pump to this circuit when pump starts, and ventilates the circuit before next sequence . Have tried two units, both fail to open this valve, and just the fuel flap open or close. Having rebuilt these units, have you discovered any external connections that operates this valve? Waiting for another second hand unit..