I have a 2002 Audi A4 Avant.
YesterdayI tried to close the boot but whenI went topush it shut it would not engage and lock.
Lock appears to be in working order but just will not engage clasp on closing.

I expect it will cost me a fortune going to Audi so hope that it has happened to someone else who can may be give me some ideas to fix by myself.
Help at the moment the boot is stuck down with black tape!

Thank you, Lydia

 

I just had the same on my 2003 A4 Avant. Suddenly the lock wouldn't engage, the trunk stayed open, and the "Open trunk indicator" on the instrument panel was on. The Alarm system didn't work, obviously, as the trunk lid was open.

I still heard the sound of solenoid in the lid, so I thought it was not the electical system.

Here is what I recommend:
#1. First spray WD40 into the lock on the trunk lid. Move the locking hook back and forth a few times. Mine was not locking due to some plastic parts inside the lock that were stuck. The WD40 helped to losen those parts inside. Chances are that this should be enough.

#2. If #1 doesn't work, you will have to remove the boot liner and see what's going on.
2.1. Remove warning triangle
2.1. Remove 2 torx screws in triangle compartment
2.1. Remove two more torx screws left and right in the lid liner.
2.3. Pull the lid liner down with moderate force.
2.4. Between the liner and the frame, locate 4 mounting brackets fastening the liner to the lid. I unfastened then with a big flathead screw driver as I didn't have the Audi tool.
2.5. I had enough space to see that the solenoid inside was working fine, no issue there
2.6. I unhooked the cables from the actual locking mechanism, carefully.
2.7. I opened who bolts and removed the lock and inspected it to see how it works. It's pretty simple, but some platic parts was stuck
2.8. I lubricated the lock throroughly and checked that it would lock.

I put it all back together, and it's been working since!