I am STILL having problems even after putting a new battery pack in the 'siren' under the hood. When my troubles first began (previous post) the car would not lock every time, and I replaced the siren with a used siren. That made solved the problem for a short while.

When the locking problem returned I opened-up the replacement siren and its circuit board was not damaged because the battery had not leaked, so I had a new battery made and installedit into the siren. And again everything functioned properly with locking sytem...but only for a few weeks.

Now I sometimes have to unlock the car with the key blade because I cant get the car to respond to the key command. And when the car wont lock after several pushes of the button I try pushing the unlock button, if the car responds and 'unlocks' the unlocked car then the next attempt to lock the car will be successful....but not always. And sometimes if the car wont lock, turing the ignition on and off will cause the locking attempt to then be successful...but not always. There seems to be no consistent pattern to any of this.

IF (big if) the siren with its new battery is functioning properly, what other components of the locking system are there that might be the culprit ? The one X factor in this situation is that I have only one transmitter key, so following the logical step of ruling out the transmitter by trying the spare transmitter is not possible.

Ideas, Mr Spock ?

 

Reading this variously I thought:

1. Bad key, as you get to toward the end. You have no other to test it against. Too many bad stories here BTW about people then losing the last key and in a world of hurt. I would suck it up and pay the man for another key. One programming charge for multiple keys BTW, so perhaps buy insurance too?

2. So, where's your cell phone in all of this? I've documented and others have confirmed for years, phones and Audi keys don't get along well. More an issue w/ keyless, and not clear in your post if your issue is w/ keyless or remote or both. Anyway, try separating the kids into opposite pockets if they aren't already. Any time mine doesn't cooperate, its usually the two have gotten together again.

3. I assume your main car battery is good? Remote function is terminated as power gets low. Keyless is lost before regular push button remote IIRC. Another clue when/if I leave lights on or something--doors don't open keyless as I approach.

4. Key battery too of course that you don't mention. The little light in it is lighting up when you use it? If not, new key battery.

 

I had a recent battery in my key but, per your post, I looked to see if the green indicator light was lighting-up when the buttons are pushed...it was not. When I checked, the
voltage was 3.15 V. I checked a new battery and it read 3.36 V, so I put it in my key. Now the car locks and unlocks just as it should. Just the difference between 3.15 and 3.36 V...little things mean a lot sometimes !

I guess that the excess of button pushes during the period of time I was having trouble with the siren ran the battery down like a much longer period of time of normal use. However, my indicator light still doesnt blink , but that may have to do with the fact that my key is pieced together like Frankenstein. It is a Bentley 3 button key (only in my case the "B" is for my last name) with my A8 circuitboard inside.

So, for now, all is well in central locking.