I have a P reg 1997 A6 Avant 2.5 TDi SE. The car is manual and climate controlled. It's basically a re-badged 100 I have no heat coming into the car at all. The heating system blows cold air all the time. I have had the car round to my mechanic tonight and his experience is that the likely problem is the control panel in the cars dash. However, he does not want to condemn the panel until he knows exactly what could cause the problem. This is where you lot come in When increasing or decreasing the temperature via the control panel, there does not seem to be any movement in the flaps that allow the hot or cold air to come into the car. Both of the water pipes are hot. When selecting the air con, there is no clunk of the compressor kicking in or no drop in revs. He is not too sure if the system needs to be re-gassed. Does the compressor work if there is no gas in the system ?? Are there any valves/fuses etc that could fail that could give the impression of the panel not working ?? Any help appreciated be as technical as you like I will print off the replies so that my mechanic can see them for himself. Thanks in advance.