Audi Repair: central locking fault., vacuum lines, audi a6 avant

Question
QUESTION: I have a problem with my central locking, none of the remotes work and the drivers door only unlocks when i use the key in the barrel.But when i lock my car with the key in the barrel all the doors will lock if  i have opened more than 1 door manually.

ANSWER: Sounds like the mechanisms may be OK.  Try unlocking the drivers door with the key twice quickly, if this unlocks all the doors then the problem is likely only the remote keyfobs or the receiver.  Did you check the battery in the key?  Let me know,  Jan

---------- FOLLOW-UP ----------

QUESTION: Forgot to mention i have an audi a6 avant.
Tried replacing the batteries and unlocking twice quicly with the key as instructed in manual but still the same.
Any other ideas?

Answer
Next I would check all the fuses, bust to do this with a fuse checker or a multimeter.  The central locking module is all self contained, and should be positioned in the rear of the trunk area or possibly under the driver's seat.  I only have A4 manuals handy at present.  The module will have some white or green vacuum lines as well as electrical connections going to it.  I would check that it is getting power; beyond that I am not too familiar with this module, other than that it does not fail frequently; I know that doesn't help you...  Let me know,  Jan