HVAC Issue

[CornersWell]

All,

Any thoughts on this are welcome.

Recently had the RS6 in for a LOT of work. Got the car back and parked it due to my travel schedule. Just returned home and am starting to run the car a bit.

First problem is the washer fluid isn't coming on call. I think I can troubleshoot that, but the other issue is the HVAC system.

I suspect the control is going bad. We replaced all 3 of the activators last year, due to the fact that they didn't seem to be blowing correctly. Then, when the car went in in September, it was on the list, again, because one side was blowing cold air, the other side blowing hot, and the center not at all. That was when it was warm, so I needed cooling. Now that it's cold, I need heating, and the same odd behavior is happening: driver side blows hot, passenger blows cold, center isn't blowing at all. I also notice that the "Econ" button is illuminated all the time, and I cannot turn it off. Even if I can get it to turn off, it turns back on without me touching it in 1-2 seconds. All of this makes me think it's a computer malfunction. It is a 20-year-old car, so I suppose it shouldn't come as a surprise, but you'd think that since I've had it in 2x already for HVAC issues, that it should be in good working order.

Anyway, if anyone has any recommendations or suggestions, happy to hear them. I was thinking of buying a spare control unit and seeing if that fixes the problem. Standard A6 component, I think, but they seem to be rare. One on eBay, but no others I can find around.

Thanks,

CW

[hahnmgh63]

Are you getting a code? Other than using Vagcom I thought there was a procedure for putting the Climate Control head into some kind of diagnostic mode? Anyone?

P.S.
Might be a start, now we just need to know what they mean?
https://www.youtube.com/watch?v=rgQtRE_Pwbs

[CornersWell]

Yeah, interesting. But, I have no idea what I just watched!

I haven't yet run VAG.

CW

[hahnmgh63]

Don't know if it works as I'm over 2,000mi from my car but this is what I found:

Accessing On-Board Diagnostic codes
Press and hold the recirculation button. Then press the manual flow control up arrow. You should see a 1c. Press the temperature up ("+") or down ("-") buttons to select a code number. Then press the recirculation button again. The value should display. Press the temperature up or down button again to display another code.
NOTE: Air Flow Motor (V 71) and Potentiometer (G 113) are not installed in USA/Canada vehicles. Disregard values displayed for these components.

Code Displayed Value
1 System malfunction - displayed as a Diagnostic Trouble Code (DTC), see chart below

2 Digital value of Interior Temperature Sensor, in Headliner (G 86)
3 Digital value of Interior Temperature Sensor, in Instrument Panel (G 56)
4 Digital value of Fresh Air Intake Duct Temperature Sensor (G 89)
5 Digital value of Outside Air (Ambient) Temperature Sensor (G 17), front
6 Digital value of Outside Air (Ambient) Temperature Sensor
7 Digital value of Ambient Temperature Sensor At Fresh Air Blower (G 109)
8 Digital value of Temperature Regulator Flap Motor Potentiometer (G 92)
9 Delta value of Temperature Regulator Flap
10 Non-corrected specified value of Temperature Regulator Flap
11 Digital value of Central Flap Motor Potentiometer (G 112)
12 Specified value of Central Flap
13 Digital value of Footwell/Defroster Flap Motor Potentiometer (G 114)
14 Specified value of Footwell/Defroster Flap
15 Digital value of Air Flow Flap Motor Potentiometer (G 113)
16 Specified value of Air Flow Flap
17 Vehicle Speed (km/h)
18 Actual Air Blower voltage (Volts)
19 Specified Fresh Air Blower voltage (Volts)
20 A/C Compressor (A/C Clutch) voltage (Volts)
21 Number of low voltage occurrences, non-transient
22 Cycle condition of A/C Refrigerant High Pressure Switch (F 118)
23 Cyclings of the A/C Refrigerant High Pressure Switch (F 118)
24 Cyclings of the switches, absolute non-fluctuating
25 Analog/Digital value, Kick-Down Switch
26 Analog/Digital value, Engine Coolant Temperature (ECT) Warning Light
27 Coding value
28 Engine Speed (RPM)
29 A/C Compressor speed in rpm (Equals Engine Speed x 1.28)
30 Software version
31 Display check (all segments of A/C Control Head display light up)
32 Potentiometer malfunction counter, Temperature Regulator Flap
33 Potentiometer malfunction counter, Central Flap
34 Potentiometer malfunction counter, Footwell/Defroster Flap
35 Potentiometer malfunction counter, Air Flow Map
36 Feedback value, cold end-stop, Temperature Regulator Flap Motor Potentiometer (G 92)
37 Feedback value, hot end-stop, Temperature Regulator Flap Motor Potentiometer (G 92), max. stop
38 Feedback value, cold end-stop, Central Flap Motor Potentiometer (G 112)
39 Feedback value, hot end-stop, Central Flap Motor Potentiometer (G 112)
40 Feedback value, cold end-stop, Footwell/Defroster Flap Motor Potentiometer (G114)
41 Feedback value, hot end-stop, Footwell/Defroster Flap Motor Potentiometer (G114)
42 Feedback value, cold end-stop, Air Flow Map Motor Potentiometer (G 113)
43 Feedback value, hot end-stop, Air Flow Map Motor Potentiometer (G 113)
44 Vehicle operation cycle counter
45 Calculated interior temperature (internal software, in digits)
46 Outside (ambient) temperature, filtered, for regulation (internal software)
47 Outside (ambient) temperature, unfiltered, (internal software, in deg C)
48 Outside (ambient) temperature, unfiltered, (in digits)
49 Malfunction counter for speedometer (vehicle speed) signal
50 Standing time (in minutes)
51 Engine Coolant Temperature (ECT) in deg C
52 Graphics channel 1 - A/C compressor switch-off conditions are identified by illuminated segments of the “88.8� display. See chart below.

53 Graphics channel 2 - Climate system electrical outputs are identified by illuminated segments of the “88.8� display. See chart below.

54 Control characteristics
55 Outside (ambient) temperature, in deg C or deg F depending on setting on A/C control head
56 Temperature in deg C, from Interior Temperature Sensor, in Headliner (G 86)
57 Temperature in deg C, from Interior Temperature Sensor, in Instrument Panel (G 56)
58 Temperature in deg C, from Fresh Air Intake Duct Temperature Sensor (G 89)
59 Temperature in deg C, from Outside Air (Ambient) Temperature Sensor (G 17), front
60 Temperature in deg C, from Ambient Temperature Sensor At Fresh Air Blower (G 109)
61 Software version (latest)

[CornersWell]

So, indy says windshield washer pump not working and climate control "orifice" is blocked. A few dollars in parts, but $500 in labor to replace!

https://www.ebay.com/itm/40276708768...3ABFBM2pn_-L5j

I am planning on attempting the washer fluid pump myself (and instructions anywhere?), but I think the orifice is difficult to get to. Anyone dealt with replacing one of these before...

https://www.ebay.com/itm/39521544812...3ABFBM7JXu-L5j

TIA,

CW

[hahnmgh63]

Sorry but I completely forgot I had a couple of manuals that will probably help. PM me your email address and I'll send them to you. They are just a little over 3MB each.

[CornersWell]

Wil do. THANKS!

CW

[CornersWell]

Got your emails. Sorry. Have been swamped. Just wanted to thank you. Haven't even had time to open them, yet, but I certainly will.

CW