Re: 156 remote locking not working?
I presume the alarm doesn't go off when you open the car.
On mine the key lost sync with the car and the remote opening stopped working, but that caused the alarm to go sound too.
I was told that removing the battery and leaving it couple of hours might cure that, but my key eventually just started working again after about a week.
Another thing to check if you think the key is working is the fuse in the car for the remote locking. It might be that the key's fine but the remote locking isn't working on the car.
Finally, there have been occasions when my remote locking just stopped working for a few days on my 156 too. It happened about four times over four years of ownership. On a couple of occasions, it started working again when I stopped under an electric pylon....
Does the central locking work when you use the key in the lock (which would mean its just the remote not working) or is the central locking even dead when you use the key in the lock (which would suggest the central locking itself is faulty)?
2004 Silver Audi A3 2.0 TDi S-Line DSG (eBay!)
OEM Xenons (retro-fitted), PIAA silicone wipers, integrated Parrott CK3000 bluetooth phone kit, O2 XDA2 PDA/phone with TomTom wired GPS
Ex - 1999 156 1.8TS SP1 (1999-2003) + 2002 156 2.0JTS Turismo (2004-2006) (fell off Snake Pass backwards at 60mph...)