i know i have an a6 but i figure theres more people on a4 pages then a6, so i figure someone can help since the insides are almost the same, anyways my whole climate control unit will not come on, i checked all the fuses and there all in working order, is there a relay under the dash for this that might have gone out? i dont know what else to try, and also my stereo wont go off when i turn the key to off and take it out.. why is this? help ASAP!

 

Could be a bad ignition switch. That can cause all sorts of funky behavior.

Have you removed the climate control to check the wires in the back of the unit?

 

i checked all the connections and there good.. when i pull out the big connector from the back of the climate control unit the blower goes to high.. and this all happened right after i took out my aftermarket headunit and put the OEM one back in, how much is an ignition switch and is it hard to install?

 

Ignition switch electrical component is less than $50 from the dealer and it's not that difficult to install, it just requires removing some dash panels and the lock barrel. If it's an automatic, this task can be a bit more of a hassle.

Try this:

Obtain the Radio code first! Plug in the OEM head unit and climate control. Cycle the ignition key on then off. Pull the battery negative and then the positive cable and let the car sit for at least an hour, overnight if possible. Better yet, remove both the cables and attach a jumper between them and let it sit overnight (insulate the battery from the cables!!). What this does is let all the computers' capacitors drain out and thusly erases all the memory. This is called a hard reset (or a "German Reset")Check and see if it's still giving you a problem in the morning.

 

tried that and didnt do anything, left it off over night.. but i was wondering if maybe the fact i removed my aftermarker flip up dvd player may have been wired to something ?

 

Hm. Hamstermarket components wired in can definitely cause issues. Sounds like you should break out a wiring diagram and a multimeter. Check continuity of the power and ground to the HVAC unit.

 

where can i get a wireing diagram ? and the HVAC is the climate control unit right?

 

Bentley publishers has them. HVAC is heating ventilation air conditioning control unit, yes.

 

where can i get this "bently publishers"?

 

http://www.bentleypublishers.com/
or
http://www.ross-tech.com/products.html

Maybe if someone's feeling generous, they can e-mail you a copy of the diagram you need. Unfortunately, since I no longer work for Porsche and Audi/VW, I've lost all access to wiring diagrams and have yet to purchase a manual for myself. I'll get around to doing it soon. I hope.