MP3Car.com - View Single Post - HVAC Control on Car PC through Serial Port.

h3rk · 07-06-2008, 04:40 AM

Quote: Originally Posted by Civic Modz

Ok, so you dont want to use a PC. You want an independant climate control but just utilizing the buttons/knobs and LCD of an Audi right? Most modern climate devices are quite complex the use numerous sensor in the cabin and engine bay. For example my brother has an 96 quattro, if you turn on the heater the fan will not turn on until the engine is warm enough. To utilize the same electronics in the audi controller you would have to get all the sensors that are used including any additional outputs. If you have a look at the connector of the climate I assume you might find about 20+ wires connected to it. Its possible but a big job (a schematic or wiring diagram will make it a bit easier). An easier way is just to use the dials and buttons of the audi and interface them to you climate system. This way you would be bypassing all the electronics from the audi (you would loose the LCD, unless you add your own or work out how to control the original one). Post a pic of your climate system in your car.

I can support that statement, I've been at it for a while. In fact, I've been sitting here tonight working on converting both an automatic and manual version of a factory climate control head to schematic, to ensure my tie in points and methods will work properly. It gets pretty complex. Like this particular circuit I'm tracing has this votage divider circuit used in the A/C compressor request line that takes the input from the intake temp sensor and compares it to a reference current. The connectors on the back total 36 pins.

Good luck with the project, unfortunately for you most of what you'll find here is PC related interface ideas and implementations.... I still wonder what happened to Mastero.

07-06-2008, 04:40 AM	#551
h3rk FLAC Join Date: Oct 2006 Location: Las Vegas Posts: 1,287	Quote: Originally Posted by Civic Modz Ok, so you dont want to use a PC. You want an independant climate control but just utilizing the buttons/knobs and LCD of an Audi right? Most modern climate devices are quite complex the use numerous sensor in the cabin and engine bay. For example my brother has an 96 quattro, if you turn on the heater the fan will not turn on until the engine is warm enough. To utilize the same electronics in the audi controller you would have to get all the sensors that are used including any additional outputs. If you have a look at the connector of the climate I assume you might find about 20+ wires connected to it. Its possible but a big job (a schematic or wiring diagram will make it a bit easier). An easier way is just to use the dials and buttons of the audi and interface them to you climate system. This way you would be bypassing all the electronics from the audi (you would loose the LCD, unless you add your own or work out how to control the original one). Post a pic of your climate system in your car. I can support that statement, I've been at it for a while. In fact, I've been sitting here tonight working on converting both an automatic and manual version of a factory climate control head to schematic, to ensure my tie in points and methods will work properly. It gets pretty complex. Like this particular circuit I'm tracing has this votage divider circuit used in the A/C compressor request line that takes the input from the intake temp sensor and compares it to a reference current. The connectors on the back total 36 pins. Good luck with the project, unfortunately for you most of what you'll find here is PC related interface ideas and implementations.... I still wonder what happened to Mastero.