The heater on my 300CD broke along time ago when the Climate control amp crapped out on me, and I ended up having to take it out. I havn't replaced it yet, and shudder when I think about the $125 for a new one and then the AC Servo crap out on me, and then having to spend $1400 for a new one . Anyways, today I am going to try and find a used climate amp, however I found a few kits on the internet that do away with the AC servo and such. I found one at **************.com for $89, which is just a bypass valve, and a manaul control cable to control the heat. Then there is this digital replacement at Performance Products for $699. What do ya'll think I should do???