I was trying to get seatbelt warning light/beep on in my A3 SE 1.8 2001.
However I think there may be no sensor in it.
I've enabled it according to the wiki and it seems that, although the seatbelt warning light comes on when the key is first turned, it goes out within 10 seconds and plugging seatbelts in and out makes no difference to the light.
I assume from this my car hasn't a sensor, yet seems to allow me to enable the light on the dash. Is there anyway to check if I have seatbelt sensors?