How do i find out the part number for the heater control panel on my wifes 2002 A210. It has a faulty switch, so i want to replace the panel (3 circular dials & two push buttons - one for recirc' & one for air con). Ive found several on ebay, but not sure which one to buy. From what i can see, there's two types - those with air con & those without-presumably, the ones without air con just have a dummy button in place of the real air con button? Ive found one with the PN 168 830 13 85 on & another 168 830 12 85. A local motor electrical specialist is going to fit it for me, but i just need to give him the right part. Help!