Audi Repair: cluster and blowers, temperature control unit, vent air

Question
QUESTION: Hi,

2 annoying problems with my 96 A4 2.8. First I am losing bulbs in the instrument cluster. From 0-120 MPH is completely out. Can I easily remove the cluster and replace the bulbs? Also, my defrost, panel and floor buttons do not do what they are supposed to do. For days or weeks I will have no dash vent air, then it will start working but I have no windshield defrost vent! Occasionally they all work as they should. What can I check for this? Oh, one more...the temp and fan display windows flash on and off, they work sometimes when i tap the window itself.? I checked all fuses...good to go.

Thanks so much!

ANSWER: The bulbs are replaceable, but you have to get the right kind.  Cluster is held in with 2 screw at the bottom of the cluster.  Sounds like the pneumatic adjustment control or the control unit itself is malfunctioning, can you identify which one?  It amy be a simple vacuum leak in the system.  I would get the system checked at a shop for leaks and proper performance.  The lights flashing on and off sound like a poor or loose connection.  Check around the area where you tap.  Let me know,  Jan

---------- FOLLOW-UP ----------

QUESTION: Thanks Jan,

The airflow is fine, I think it must be the control. Is that an easily replaceable part? The temp display windows...can they be removed and checked for connection problems? I will search the web for the cluster bulbs and do that myself. I'll let you know how I make out.

ANSWER: The control is seperate from the servo's that control the flow.  The problem could be in either place.  You can remove the temperature control unit out of the center console and check the connections.  Let me know how you get on,  Jan

---------- FOLLOW-UP ----------

QUESTION: I found this on Ebay, will this fit in my 96? It looks identical. I'm thinking it's the whole computer, perhaps not sending the proper signal to the servos? Is this somethin a novice like me could replace? Looks like just connecting a lot of wires...

http://cgi.ebay.com/ebaymotors/97-98-Audi-A4-OEM-Auto-Climate-Heater-Control-Pan

Answer
If it looks identical, this may be an easy way to diagnose the problem.  If it fixes the problem you are golden, if it doesn't then you have eliminated the control system and you can move to the servo's...  Looks like a winner to me.  Let me know,  Jan