I purchased by mistake (didn't look catalog number) Audi Concert II radio which was originally in Audi A3 8P. Part number is 8P0 035 186 and for B6 its 8E0. The issue is with radio dash keys illumination which don't work. I've had aftermarket Grundig radio earlier in my car and wanted to upgrade it to original Concert II and now this happened. Radio display is lit but the keys on dash aren't. Is this radio for cars with CAN-BUS which is controling radio dash backlight? My car dont have board computer and I dont see any illumination pin on the back of device.