audi a6 avant, problem with oil low level light, and bulb replacement

[darcar]

Hi all,

Does anyone know why my oil low level warning light comes on, even when the oil level is ok!!!!!!
also can anyone inform me how to replace interior light bulb which are housed in the centre, my car is a 2007 audi a6 avant, 2 litre model, tdi.

thankyou . darcar