Power Door Lock issue

[cope09]

I recently purchased 99 A4, 2.8 Quattro with 130k.
The car is in great condition with one exception aside from the Key Fob not working...
When i try to manually unlock the doors (turning key to left/counter-clockwise), the locks will rise, then I hear a vacuum-type sound and it sucks the locks back down again. Even more odd...the only way in my car when the doors are locked, is to unlock them by turning the trunk lock to the left!

Has ANYBODY ever heard of this happening? How does this system work? why would I only be able to open the locks via the trunk and not the drivers or passenger doors?

Thanks in advance for any help you can provide!!

--Chris
99 A4 2.8Q
and
05.5 A4 2.0T

[strudel]

Hi,

I have been searching the forum for this very problem. You are the only one to state this issue with no replies. Did you ever resolve the issue?

My key fob remote works perfectly. But when I try to unlock the driver or passenger door with the actual key it fights me with resistance and locks back up immediately and rearms the alarm system.

On the other hand when I try the key in the trunk it will unlock the driver's door with one left click and all the doors with two left clicks. I find this odd. A alarm system tech who works on Audis thinks it is the sensor in the trunk that is causing the door problem fooling the ECU or comfort system as it may be the culprit into thinking there is a problem with the doors.

If anyone has any ideas I would appreciate it. I will borrow a VAG Com system from my son in laws shop and see if there are any codes or we can reprogram the system. JS