I have a 2003 M45 with navigation system. At first failure of all sources at the panel containing the screen completely failed intermittently. Restarting would correct this situation, but now there is almost complete fauilure. When the system fails, the AC blower starts, and it will heat as well as cool. I was told by an independent shop that a "module" was the problem and that only an Infinity dealer could replace at a very steep price, since they were the only ones that could program the module. I was also told that this was not an uncommon problem and there might be a maintenance notice. Can anyone help me with this problem?