kainy

Short version

Both my keys stopped locking the car from the key fob. Everything else works - unlocks fine and opens the trunk lid. Locking with the key from the driver's door is working too (the comfort locking too for the windows and sunroof), as well the buttons on the driver's door lock and unlock the car properly.

The car was already at a shop where they tried bunch of stuff, including testing the transport mode and programming a new key, but nothing works, and they offered to add a new external module for the locking bit, and to manufacture a 3rd key with all options working. But I kinda don't like this idea , for now.

When I use the locking button, it flashes normally at first, they I get rapid flashing for couple of seconds (the led on the key fob)

I've scheduled to visit the local audi dealership to see what they can do about it, but wanted to have some more information beforehand to avoid misconduct on the dealer's part...

Long version

Months ago, I did a manual to tiptronik swap on the car. It basically sat at the shop for around 3 months, I guess most of the time with disconnected battery. It also went through numerous visits to Audi for recoding. The moment I got the car, there was the issue with the locking from the key, which was present in my spare key too. I just came around to deal with it due to mainly laziness

The only other things that were not okay after the "transplant" are:
1. I can start the car without pressing the brake pedal
2. I can remove the key from the ignition when it is not on P

which is going to be part of another discussion if the dealership can't figure it out, but I guess it is just some recoding that they have forgotten (as they did for the parktronik module for example...)

LMSI-G35X

When my door locks went bad the key fob wouldn't work for locking the car. I had to replace the latches in the door on both front doors.

stuffinder

I had similar problem when I bought my '08 last Spring. VAGCOM showed error in left front door latch. My mech replaced it with New one from ebay. In my case the doors wouldn't stay locked. If I remember correctly I later found there was as mechanical override through a rubber plug on passenger door. When I locked it that way I could use the key and the rest of the doors would stay locked.

kainy

That's the thing. I have no issues with the locking mechanisms. They work fine and the car locks/unlocks properly, from everywhere except the key's remote lock button. Locking with the key manually is OK.

The service shop deduced that I need to change the comfort module, but I believe that if the issue is with it (which most certainly is, and that might explain the other two issues with the pedal and the ignition lock), then it might be just a matter of setting the correct coding.

Nevertheless I do have the comfort module from the car I took the automatic gearbox, so I'm gonna give it to the Audi dealership when they look at the car, to replace it if necessary, as I won't have the time to try it on the weekend myself.

LMSI-G35X

My car would lock fine with the key physically in the lock as well. There becomes a problem with the lock actuators themselves where they electrical contacts inside get mucked up and don't relay the signal. Well documented the problem, research it. It very well could be your comfort module, but I'd suspect the lock actuator. Do the doors lock and unlock with the buttons inside on the door?

kainy

Yes, the buttons inside lock/unlock normally, and the car locks fine automatically when in motion.

kainy

So... I forgot about another issue I have from the swap, because I really didn't think it was that big of a deal as everything seemed to work fine.

Basically I'm getting a "Transmission Park Selector Switch malfunction" or something similar (can't quote the full fault code at the moment) ever since I did the swap. The only visible consequence from that was that sometimes when I move the lever to "P", all modes on the display (P-R-N-D-S) would be highlighted, rather than just "P". Moving the lever to "R" and than to "P", fixes it every time, but even if I leave it like that, nothing really happens.

This coupled with the fact the the lever doesn't really move smoothly on some gear changes and sometimes does not pop the pin out when on "P" and I have to jiggle it, made me sure that the guys did not assemble it quite well. But until now I looked at it as a cosmetic issue that I just didn't have the time to address.

The dealer on the other hand claims that this causes the issue with the ignition not locking the key, and the key not locking the car from the remote (starting the car without pressing the pedal was by design, silly me ). When I looked at some electric schemes I found that the immobilizer does get info from the Park Selector switch, along the one from the key and various other places, so it does make sense, to a degree, that if it senses that the car is not on "P" (or there is some fault there), that it won't let you "carelessly" lock it, without doing it manually.

Nevertheless, Audi concluded that this is the problem and wanted to change both the 2 micro switches and the selector itself, which I found out meant the whole lever system, which surprisingly isn't that expensive (400 euro). Still I'm gonna disassemble it first and try to see if it really is just assembled poorly or broken beyond repair and then think of replacing it if the error continues (Audi claims the magnetic switch is moving slowly... whatever that means)