wisconsin_quat

<center><img src="http://pictureposter.audiworld.com/48795/a8_code.jpg"></center><p>
01 A8L

Problems with HVAC system... No warm air coming through vents. I've searched the forums for a good hour or more and it seems as though this has been a common problem but no one has listed a fix.

-No warm/hot air blowing through vents
-Basics settings completed (one fault listed) 00604 -Potentiometer positioning motor for air flow flap g113
09-00 - adaptation limit surpassed
-In measuring blocks, all motor and flap actual positions correspond to positions indicated by the system.
-In measuring block 19 the N175/ N176 water valves for the AC are indicating that they are closed. I believe this is where the problem is. All hot engine coolant is bypassing the heater core. I am not able to open the valves no matter what setting is established on the climate control ie.. recir, etc.

I have posted the link to the original thread from 2 weeks ago.

Any thoughts?<ul><li><a href="https://forums.audiworld.com/a8/threads/28063.phtml#156183">https://forums.audiworld.com/a8/threads/28063.phtml#156183</a</li></ul>

wisconsin_quat

Both valves are closed. I believe this bypasses coolant past the heater core.

19,0,Coolant Pump V50 -Heat Reg Valve N175 Right -Heat Reg Valve N176
19,1,N175,1=Open 0=Closed
19,2,N176,1=Open 0=Closed
19,3,V50,0=Off 1=On
19,4,Windscreen Def

ricoblanco

<center><img src="http://i255.photobucket.com/albums/hh156/ricoblanco/87-1494.gif"></center><p>"3 - Center vent adjusting motor -V102- Flap can be opened or closed by adjusting potentiometer in center air outlet -G142 (program-controlled)
If flap is open, cold air is blended with air flowing out of center instrument panel outlets

4 - Temperature regulator flap motor -V68- Flap can be opened or closed by adjusting center vent position sensor -G142- (program-controlled)
If flap is closed, only cold air flows out of center instrument panel air outlets"

Does this help at all?

ricoblanco

<center><img src="http://i255.photobucket.com/albums/hh156/ricoblanco/Flapmotor.gif"></center><p>Flap and vent motors, servicing Notes:
Mark connector for the motor when removing (danger of swapping with connectors of the other actuator motors).
For the malfunction "adaptation limit exceeded", check connector at motor, there must be no play between the shaft of the actuator motor and the connector.
Replace the actuator motor if it makes clicking or rattling noises in regular intervals (approx. every 7 minutes).
These noises originate via activation of the actuator motor via the A/C control head -E87- in actuator motor drive.
Activation occurs to maintain the flap/motor securely in one position.
To determine which actuator motor is making the noises, the different actuator motors must be connected in sequence (using VAG1598 test box and cables from VAG1594A connector test kit) to the 12 V supply voltage (B+ socket "E5" and Ground socket "E9") until a stop has been reached. (To reach the other stop, B+ and Ground (GND) must be swapped). The respective sockets from test box to the different actuator motors =&gt; page AUDI-D3-HA01-01-002-0101-159, Electrical test, test step 6.3 to 6.10 and
=&gt; Electrical Wiring Diagrams, Troubleshooting &amp; Component Locations
Notes:
With gradual implementation, only actuator motors with an additional bolt -C- at housing are supplied as replacement parts.
=&gt; Parts Catalog
This bolt is supposed to prevent cover -B- from lifting off and for the drive shaft in housing -A- to skip.
It may be necessary to remove bolt -C-, depending on the installation position of the actuator motor (the function is then performed by the bolt with which the actuator motor is bolted to the A/C housing).
Depending on the installation position of the actuator motor at A/C system, it may be necessary to shorten the rib of the third take-up point at A/C system in such a way that the actuator motor can be installed without bolt -C- or nut -D- making contact (in this case the actuator motor is not bolted on).
If an actuator motor is supplied as a replacement part, bolt -C- (M3 x 30) can be retrofitted with an appropriate shim washer -E- and nut -D-.

PaulW

Here is a picture of the regulating valves, they are the big black round things:

<img src="http://www.audipages.com/images/hvac1.JPG">

Both of them have a common connector, T3Q, which is a 3 pin connector, brown, in plenum chamber left.

I don't have a picture of the connector, but I'm sure it's right there. You can see the wires coming out of the RH unit. The connector shown is for the V50, coolant pump (after run coolant pump) and sometimes they make a lot of noise, so you can just unplug it and it still works just fine when the engine is running.

N175/N176 are powered through fuse ST3, S7, third fuse row down (yellow), 7th fuse. It's a 15 amp fuse. I would check that first.

<img src="http://pictureposter.audiworld.com/22012/relay_box2.jpg">

And I will ask again: Did you crack the high vent points on the heater hoses with the thermostat open and ensure that coolant was coming out of them?

wisconsin_quat

I was able to swap the climate control head to to avail yesterday. I did however finally catch the valves showing as open through ch 19 on the measuring blocks. I am convinced the flap is not open or is stuck in a closed position, not allowing any warm air to blow through the system. Reasoning: i did pull that fuse yesterday, unplugged the valves on a separate occasion and still no heat. Both heater hoses hot as can be, open the bleeder valve on the heater hoses and it's fierce enough to squirt further then i could whizz back in 3rd grade.. anyone have specific info on the G113 motor and its location? I checked and have the A4/S4, cabrio and 90 manuals but not the A8 manual. Location is enough for me to evaluate if I'm going to mess with it or not. Thanks guys!

wisconsin_quat

awesome, can you also post what those numbers mean so I can figure out what this corn maze is? I imagine that B is the fan and H1, G1, F and G2 and H2 are the vents. what a mess!!

wisconsin_quat

on second thought konrad lets maybe donate the car to esperinza unida and get the tax deduction

ricoblanco

I - Engine compartment (plenum
II - Passenger compartment
III - Air conditioner
A - Dust and pollen filter Installed in front flap
B - Fresh air blower -V2-
C - Evaporator
D1 - Left heater core (driver side)
D2 - Right heater core (passenger side)
E1 - Left mixing chamber
E2 - Right mixing chamber
F - Air guide to center air outlet at rear
G1 - To left footwell air outlets Driver and rear footwell
G2 - To right footwell air outlets Passenger and rear footwell
H1 - To left instrument panel air outlet and to B-pillar left air outlet
H2 - To right instrument panel air outlet and to B-pillar right air outlet
J - To defroster outlets
K - To center instrument panel air outlet
L - Air intake duct for recirculating air mode 1 - Air flow flap motor -V71- Flap closes completely in recirculating air and ACF mode and also partially at higher speeds (program-controlled)
2 - Recirculation flap motor -V113- Flap opens in recirculating air mode
3 - Center vent adjusting motor -V102- Flap can be opened or closed by adjusting potentiometer in center air outlet -G142 (program-controlled)
If flap is open, cold air is blended with air flowing out of center instrument panel outlets
4 - Temperature regulator flap motor -V68- Flap can be opened or closed by adjusting center vent position sensor -G142- (program-controlled)
If flap is closed, only cold air flows out of center instrument panel air outlets ( =&gt; item AUDI-D3-HA01-87-007-013)
5 - Defroster flap motor -V107-
6 - Left footwell flap motor -V108-
7 - Right footwell flap motor -V109-
8 - Left center vent motor -V110-
9 - Right center vent motor -V111-
10 - Rear footwell vent motor -V112-
11 - ACF flap motor -V114- In preparation
12 - Left vent temperature sensor -G150-
13 - Left vent temperature sensor -G150-

Brookfield, WI - the city of my birth! nice!! :-)