Audi TT Forum banner

Stripping and Cleaning a Door Lock - How to...?

4.8K views 25 replies 8 participants last post by  ian402012  
#1 ·
Hi, please has anyone on the forum had the need to fully strip the door lock mechanism?
Mine is seized, the reason for which appears to be a slight tear in the external door handle gasket allowing water to sit around the stainless key entry trim cover. Over time, the aluminium (Mazak?) outer barrel has furred up slightly and the Aluminium Oxide, being less dense than the metal, has expanded and seized the key mechanism.
Soaking in penetrating oil for a week has not worked, and I am now trying it in an industrial strength sonic bath for a few hours, but I must accept that it is likely I will need to fully strip it to polish back any corrosion.
So, has anyone any pictures or advice on getting right into the lock without risking breaking the relatively thin and brittle outer barrel??
Thanks,
Jon
 
#2 ·
There is a captive screw that holds the barrel mech in place behind a small rubber grommit and the outer cover comes off easily From the actual door handle. The tumbler mech can then be removed and attended to. If it’s not obvious, look up the door diagrams in the knowledge base
 
#3 ·
Might be worth a read through the Workshop Manual. You can find them here -

General Body Repairs, Exterior A005TT00220


Image
 
#5 ·
For future reference, this Youtube video might help. Link here. The video walks through the process of removing and installing the lock barrel as described in the Workshop Manual, General Body Repairs, Exterior A005TT00220 on page 88, #7 Lock Cylinder Housing. I have added it to the Knowledge Base link here.

With regards to cleaning the assembly, I would caution against using WD-40 as a solvent/lubricant and only use solvents that evaporate completely to avoid leaving any residue in the lock barrel which will lead to the accumulation of dust or dirt which will ultimately result in gumming up the lock again.

Once the lock is completely clean and dry, use a dry graphite to lubricate the lock. Simply apply the dry graphite onto to the key blade and insert the key into the lock. Run it and out and rotate it in the barrel. Repeat this process two or three times. Then reinstall the lock into the door. One trick for lubricating the lock while it is still in the door is to dip the key blade in rubbing alcohol, apply the graphite and run it in an out of the lock. The alcohol will hold the graphite to the key, but evaporate soon after.

I'm trying to find anything on disassembly of the barrel itself. There are repair kits for the older
VAG locks, but can't seem to find one for the Mk2 TT. :unsure:
Image
 
#7 ·
It seems these locks are manufactured by Huf Hülsbeck & Fürst GmbH & Co. KG and like most VAG Tier-1 suppliers, they are not offering anything in the way of documentation or spare parts at least that I can find. While there are repair kits available for the older VAG locks, I wasn't able to find anything for the lock used on the TT (8J) or Q7.

Out of curiosity, I checked a couple of Russian websites as these guys often come up with "out of the box" solutions to various automotive challenges. But in this case, no one mentioned a repair kit.

However they are resorting to either soaking the entire lock assembly in ultrasonic baths of solvent, or as shown below for a Q7 lock assembly, boiled it in water with citric acid; "WD-40, Coca-Cola lemon has done 100%!"

Image


This post is from a Russian Audi TT Mk2, where the author describes the same process but also includes some disassembly instructions.Personally, I would not boil the plastic seal it at all as it might embrittle it.

Image

Image
 
#9 ·
I have toyed with buying an ultrasonic cleaner for ages. Just looking through Amazon and eBay, you can pick up a brand new, 3 Ltr. ultrasonic cleaner for less than 100-Euro. This might be a nice Christmas gift for myself this year as I can think of a few things in the shop that could use a good cleaning! ;)
Image
 
#12 ·
I have toyed with buying an ultrasonic cleaner for ages. Just looking through Amazon and eBay, you can pick up a brand new, 3 Ltr. ultrasonic cleaner for less than 100-Euro. This might be a nice Christmas gift for myself this year as I can think of a few things in the shop that could use a good cleaning! ;)
I have used mine quite a bit with small motorcycle parts and it was invaluable back when my sons were racing Rotax Max karts, and forensically clean carbs were the order of the day. I have a Fisher Scientific unit that would have been an eye watering cost new, but well priced secondhand, and has worked faultlessly for over 10 years now.
 
#10 ·
Adding a question here, has anyone had theirs re-keyed? Also I wonder how hard it is to DIY re-key these?

I ask because my keys have never worked in the door cylinder in my TT. I have a suspicion it's because the original keys were lost and both they and the ignition cylinder were replaced at some point. The reason I say this is because there are like 4-5 keys registered to the vehicle according to the in-dash telltale.

My thinking is when the car went from owner 1 to 2 (I am the 3rd owner), only one key was provided and that person lost the key and this was the result--since it probably cost them like $1k+ to have it remedied they probably opted not to get the door cylinder changed as well. It's only speculation but why else would there be so many keys registered on the car and the door cylinder not turn? I myself did get two keys with the car, but not the plastic valet key...which again makes me think that key would no longer work in the ignition even if I had it.

I mean I suppose it's possible the cylinder is seized as has happened to Jon here (?), but I dunno it seems more like it's simply not the correct key for the door.

Previously I wasn't so concerned but now I'm thinking more about looking into it since I've had the remote strangely fail to operate the unlock a couple times recently and I know what a PITA it can be to get in this car if the fob doesn't work or battery dies, etc.
 
#11 ·
Adding a question here, has anyone had theirs re-keyed? Also I wonder how hard it is to DIY re-key these?
I ask because my keys have never worked in the door cylinder in my TT. I have a suspicion it's
I mean I suppose it's possible the cylinder is seized as has happened to Jon here (?), but I dunno it seems more like it's simply not the correct key for the door.
Previously I wasn't so concerned but now I'm thinking more about looking into it since I've had the remote strangely fail to operate the unlock a couple times recently and I know what a PITA it can be to get in this car if the fob doesn't work or battery dies, etc.
“Funny you should say that” on two counts -
1. If I did not know 100% for certain that these were, indeed the correct keys to this car (because I had used them in the door previously) , I would have been absolutely convinced that they were not the right keys. Not a single hint that the key and the lock were related. So, as it is essentially entirely free to pull your door lock, and clean it up (be persistent!) I would definitely try that first. If that failed, I would ask a locksmith to read the lock and key and confirm if they matched. You could be right that it isn’t the right lock, due to the extra coded keys, but worth putting the effort in to avoid the hassle. Does the key work in the glovebox? That might give more evidence.
2.See my other post on getting into the car with a flat battery and seized lock - fortunately not as tricky as It could have been.
 
#17 · (Edited)
I’ve dealt with a similar issue before on an old car I was restoring. The key mechanism was totally seized from corrosion, and soaking in oil didn’t cut it. I ended up using an industrial ultrasonic cleaner (found a great one on kaijo-shibuya.com), which really helped loosen things up. I still had to carefully strip the lock and polish the barrel, but the ultrasonic bath did most of the hard work without damaging the parts.
 
#18 ·
Over a year later and here I am just removing my cylinder now! Figured it's a good idea to finally do this (my cylinder is seized and won't turn with the key).

I'd note there is one crucial thing the instructions to remove the lock cylinder don't seem to say anywhere!?

In the one video linked in the KB thread on this the guy just shows turning the screw and the lock just coming out as if it were easy as pie. Well I did that (the screw doesn't fully come out either BTW, something else not mentioned) and then I was there for about half an hour trying to get the darn cylinder out of the door. Tried a lot of prying with plastic pry tools and got mostly nowhere. Absolutely it did not come out as easy as the guy does it in the video. It doesn't help the video has no voice just some rinky dink music and everything looking super easy.

I sprayed in a bunch of silicone spray was trying to hold the handle out while prying, etc. Nothing was working. What was happening was the "end" of the lock was starting to come out but the inside (towards the pull handle) was dead stuck. I was very convinced there had to be another screw holding it or something. I kept prying wiggling, hoping and praying...eventually the thing popped out a bit violently and thankfully I was both using plastic pry tools and a cloth between there and the door and so no damaging.

But yeah it came out. But the frustrating part was it was quite clear why it didn't come out...after it came out.

Just leaving this here so it helps other ppl in the future.

Essentially once you loosen the T20 screw, you have to push on that screw because that whole thing is on a sliding mechanism. Sliding it allows the lock to be released, not just/only loosening the screw. If you don't slide the cage or whatever you want to call it, the lock will not come out. Well I suppose it will come out after you frustratedly start jiggling, prying, etc. such that you cause the slide to move far enough it eventually comes out...like I did lol. But this all could have been made easier by highlighting the sliding mechanism inside the door handle.

Anyway that said now I'm gonna have to try to soak this thing in something to get it freed up. Will say how that turns out a bit later!

The crucial line in the manual BTW is here:
Image
 
#19 ·
Well I've had it sitting in CLR for about an hour, lots of bubbling and ton of crap came off it, outside of the lock looks squeaky clean now except the bits of the solid lubricating grease left in places like the spring.

However...lock still will not turn 😟 Tried a few times during the soak and no dice. I also put a tootpick in the end to "prop open the door" though I'm sure the CLR was getting inside anyway. As said everything now looks clean, the CLR in the cup I used thoroughly dirty/dark the back of the look is at moving within that mm or so it does without the cylinder being released via the key. The tumblers in the lock all sounds like they are moving when I slide the toothpick in there...

Really at a loss here unless the key really isn't the right key for the lock 🤔 It's really looking like that at this point but not giving up just yet. I've poured out the dirty/used CLR and put it in a smaller cup with more/new solution and will wait another hour. I'll clean it out after with alcohol and/or brake cleaner too but if still doesn't turn it might have to go to a locksmith because I feel the way the mechanism moves now it should be turning with the correct key.

The cylinder date code is January 2012 and the car was made a few months later so I do believe it's the original...I'm just not sure about the keys being original because of how many keys show programmed to the car on the DIS.

Thinking about if the case is I do need to re-key this... I see the pics of the "dismantled" lock above but they didn't take the cylinder out of the housing there--I'm guessing one has to put a flat blade in the slot on either side and punch out that piece there? And then the tumbler/cylinder will slide out (with of course the springs, etc flying everywhere lol, so need to contain it). But you probably need a special tool to put the cylinder back plus have to get a source for the lock "pins" I guess best to leave to a locksmith.
 
#20 · (Edited)
Okay so my lock seems to be fully cleaned at this point... I wish I had taken before pictures to show the difference but it's honestly totally different now than what it looked like when I pulled it out--night/day difference!
Image


But the lock still will not turn! TBH I really feel like it's not the correct key at this point. The lock "feels" like everything should move, it feels the same as when I intentionally put my TT key into my A3's door cylinder, meaning the wrong key in a working cylinder. I'm still not 100% sure on that since everything has 2012 date codes on it which would be correct but that doesn't eliminate the possibility the key blades (alone) were replaced on original remotes.

At this point I want to dismantle the lock further, does anyone know how the tumbler comes out of this? I've tried looking up info online and come up blank. I've found YT videos showing how to repin (rekey) a VAG ignition cylinder but not a door cylinder. I've found a rekeying kit for about $60 USD that contains pins for Audi/BMW/MB cylinders but without a way to take this apart that would be a waste of time. The only problem is general guides on pulling an automotive cylinder out, say you need the proper key to pull out the cylinder (so the pins are "flat" which makes sense)--even if the cylinder doesn't turn you need to have the correct key...either that your you need to pick the lock obviously--which is easy with the right tools but I don't want to get into buying a Lishi as well as I don't have one.

I can't tell if the cylinder is supposed to come out after dismantling the rest of the "tail" section (as shown in the various pics above) and then just removing the cosmetic cap and pulling it out...or if there's more that has to be done? The metal in the slot here (can be seen on both sides) almost makes me think this has to do with getting the cylinder out, but I'm not sure? I'm thinking maybe you have to punch it one direction or the other and it might release the cylinder?
Image

Image


Also, is the key code printed on the lock shell anywhere? I think these have 6-7 pins just looking at the key? First I was thinking the "N0502772" might be it but looks like the lock in the pictures above have the same number so clearly just a p/n. I guess it would be stupid for them to print the code on the lock anyway.

Would appreciate any info on this!
 
#21 ·
Well Good Friday all. By the grace of God...my lock started turning suddenly! 😁

Not sure what happened but I went to just "give it another try" and I just put the key in and it turned! 😊

Didn't have to get into the cylinder after all and it's def. the right key. I can only think there must have been one last pin that was stuck that released (because I think I was hearing/feeling like 6 of them move with the toothpick). Now just to put it back together, lubricate it properly and get it back in the door!
 
  • Love
Reactions: Steviejones133
#22 ·
@TT'sRevenge - well done mate, perseverance paid off ‘eh?. Get some graphite powder in the barrel and give it a good working in with the key/turning and you should be all set 👍
 
  • Like
Reactions: TT'sRevenge
#23 ·
Yeah I'm quite surprised I was thinking it was going to be a trip to the locksmith if I couldn't figure out how to get into this thing. Then I just picked it up now and boom it's turning!

However in Steviejones133 fashion I realised I must do something else now...LOL. So the "door handle cups"...I think you know where I'm going with this haha. They are "scratched" up to heck as would be expected for that area on a car with handles like this. While I did fully detail the car and ceramic coat it when I got it, as you know there's only so good you can get under the handles since you can't get a machine in there too easy. But I had no idea the handles were this easy to remove--that same "cage" in the door allows the handle to just pivot out--if I had known I'd have done this way back then. Anyway now that this one side is out I can now proceed to get a good polishing done in there and will have to do the other side too. Probably will have to wetsand the driver side I think. Then probably get some door-cup protection film from Lamin-X to put on afterwards :)

Doing one thing...you always somehow find something else to do lol!
 
#26 ·
Click to expand...
Hi , had the same issue with the barrel seized.Sprayed it with dry pfte lubricate a couple of times..Then took the 2 springs off the cylinder barrel. Grabbed the cylinder with a pair of small pliers then held the barrel at the same time .One good turn and it unseized the cylinder. Happy days... the key now turns easily. Saved myself a couple of hundred pounds for a new barrel....from the dealers or an 2nd hand barrel off Ebay,which you would have to get repinned or even reprogrammed...