Hi all,

I have a 2003 a6 avant 2.5tdi quattro. Fitted were 17" alloys but because I live in a very snowy area I recently replaced the alloys with 16" steel wheels and hankook snow tyres. About 10 minutes after driving away the engine management light came on. I was on the motorway and needed to get home. The next day I drove the car and the light came on, stayed on an then after approximately 10/15 mins the light went off and stayed off. Then today I used the car again the light again came back on. I have read on another site that it could be to do with tyre pressures or the wheel size not being recognised but the person wasn't too sure. Does anyone have any ideas?

Also the brake change warning came on today so I am going o change the pads but where I live it seems copper slip is neither available or used (in garages) does anyone know of an alternative? Thanks in advance.