Oil can light is on

[Veg]

But I have great oil pressure and loads of oil in it! Any reason why?

Now it's off and I've done nowt!

[bluequattro]

Poor connection, probably frayed wire on the sensor.
My Tdi did same a few weeks back.
Checked oil
Put new sensor in
Came to so 2nd sensor and the wire fell off the spade as I touched it!

[rxl]

But I have great oil pressure and loads of oil in it! Any reason why?

Now it's off and I've done nowt!

sensor OK?

[UrS4boy]

20VT oil pressure sender info

But I have great oil pressure and loads of oil in it! Any reason why? Now it's off and I've done nowt!

Written for the AANs but applies to the ABY and ADU (and probably the 3B):

http://forums.quattroworld.com/s4s6/msgs/96161.phtml

[Veg]

Neat article and I've changed the F1 sensor so my money is on a duff connection or duff switch......

[Error404]

I had this once, changed both pressure sensors and checked the wiring thoroughly - no issues.
Turned out to be a Autocheck itself. Not likely to be the problem, but if all else fails might be worth a thought

Normally the cause is the cotton reel sender gone bad IME. You can test this by pulling off the connectors as the sender pulls to earth when it triggers the warning.

HTH