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opposite_lock
07-12-2007, 08:15 PM
Hi
Have a '99 A4 Avant 1.9TDi. The air-con will only blow cold air, and the controls for directing the air to screen / face / feet do not respond.

The blower works OK, and the control screen all lights up OK. When the engine heats up, the blower speeds up as normal as hot water becomes available. However, no matter how high or low a temperature I select on the climate control, the air getting blown out the vents stays the same cold temperature. The engine gets up to 90 degrees as normal.

Took it to an air-con guy this afternoon, who plugged in to the diagnostic socket. The codes indicate that there is no power to the footwell flap, temperature control flap, or to the centre flap of the heater assembly. He checked fuses and they seem to be OK. We are not sure how to proceed.

Am thinking of control unit fault / faulty relay / blown fuse elsewhere / dislodged connection etc, but good info this detailed is hard to find in the manual.

Any ideas??

audimad
08-12-2007, 12:39 AM
It sounds like your climate HU is faulty. As there are no fuses or relays in between the unit and the motors

opposite_lock
08-12-2007, 09:54 AM
Could you confirm what you mean by Climate HU? Is it the complete control unit including display panel, or is there some part that can be replaced separately?
Thanks very much for the advice.

opposite_lock
08-12-2007, 08:30 PM
Audi quoting £570 (part only) for climate control unit!!

a8 tech
08-12-2007, 08:43 PM
carry out a basic setting reset and all the motors will open and close and return to default,then test the operation,its very rare a climatronic unit fails but sometimes the motors stick or the rods pop off.There is enough info in measured value blocks to determine whats going on.

adamss24
08-12-2007, 08:52 PM
It sounds like your climate HU is faulty. As there are no fuses or relays in between the unit and the motors
Hi audimad, any chance you could post a few pics of your car ? Looks verry good in your avatar....Sorry for hijacking the thread !

opposite_lock
08-12-2007, 09:19 PM
The aircon specialist I took the car too did a couple of resets and error memory clears but the same error codes (no voltage at various flap servomotors) kept coming back.

a8 tech
08-12-2007, 09:26 PM
Then its time to disconnect the motor and test the 5 volt supply,if supply ok and voltage changing when the selected motor is altered with climatecontrol then check the linkage and flap are moving free.If the voltages are ok and the flap and linkage ok then its the motor or motors,if the voltages are not ok test the resistence of the wires back to the control unit also short to + and - and mutual shortbefore condeming the control unit.Also if possible swap the control unit from another vehicle bering in mind to record the code of both the control units so you can recode to the original value and test it that way,Good luck i think ive given you all you need to resolve your fault.

opposite_lock
09-12-2007, 02:07 PM
thanks a lot for all the help

audimad
11-12-2007, 07:35 PM
Hi audimad, any chance you could post a few pics of your car ? Looks verry good in your avatar....Sorry for hijacking the thread !
http://s38.photobucket.com/albums/e123/audimad/?sc=3:D

opposite_lock
16-12-2007, 02:54 PM
just to let you know, if anyone else has the same problem, a second hand climate control unit has just solved the problem (and cost a lot less than audi were going to charge!)

audimad
16-12-2007, 04:04 PM
Glad to be of service

Abbs985uk
20-02-2008, 06:37 PM
Having same problems except my climate head unit on a 1999 A4 has died completely, will not even switch on!!

Any ideas where to get a second hand unit from?

fifehibby
21-02-2008, 04:39 PM
Then its time to disconnect the motor and test the 5 volt supply,if supply ok and voltage changing when the selected motor is altered with climatecontrol then check the linkage and flap are moving free.If the voltages are ok and the flap and linkage ok then its the motor or motors,if the voltages are not ok test the resistence of the wires back to the control unit also short to + and - and mutual shortbefore condeming the control unit.Also if possible swap the control unit from another vehicle bering in mind to record the code of both the control units so you can recode to the original value and test it that way,Good luck i think ive given you all you need to resolve your fault.
How do you access the motor(s) and flaps?

fifehibby
21-02-2008, 05:06 PM
Can anyone tell me how to access the motor(s) and flaps??:D

opposite_lock
21-02-2008, 07:30 PM
Hi
Can't say about getting into the motor and flaps, because I never had to go that far. But to answer the previous question, I got my 2nd hand control unit from VW-Audi Spares in Magherafelt (Northern Ireland) (Tel. 028 7963 1214). I was able to try it there before I bought it too. Don't know if they'd post one if you aren't in NI.
I also got quotes for 2nd hand ones from allaudi.co.uk and partsgateway.co.uk but didn't go with them so cant offer any advice about them.
Good luck

Abbs985uk
21-02-2008, 09:23 PM
Thanks, have ordered one which is meant to have a 3 month warranty so fingers crossed.

i assume once the radio is removed is it relatively easy to change over? Is any programming required or the like?

Many thanks again.

opposite_lock
22-02-2008, 08:43 PM
With the radio out of the way, and the surrounding trim face panel off, it was easy enough. My manual said that you just need to give the unit a shove from behind and it will spring out, but I had to help it a bit more. Mine had 4 spring clips (2 above, 2 below) that, as the control unit goes into its rectangular space they ramp down and then spring up behind the panel. Theres no ramp angle to just shove them on the way out though, so I had to get a little screwdriver in to lever the clips down a bit to help - hope this makes a little more sense when you have the new unit in your hand.
Regarding programming, the books say that stuff needs reset and codes need entered but my aircon guy reckoned that was only if you got a brand new unit. If you are getting one thats been working in another car then he thought it'll sense the new flap positions etc and be OK. Couldn't guarantee this will work, but it did for me. I did however do the switch at a time when I knew I could visit the aircon man with his laptop to do a reset if required.