RobTR8

HVAC stuck on vent, no defrost, no footwell. What's up?

scribble

Sounds like your flaps motor(s?) is stuck.

Happened to me last year during the winter, but miraciously fixed itself this spring.

MiniMan

The Automatic Climate Control which appeared in several models includes an easy-to-use 61-channel OBD (On Board Diagnostic) display which can be accessed without the use of special tools. This function can be an indispensable tool in diagnosing problems with the climate control system. Owners of cars without automatic climate control must have error codes read with a VAG 1551 Scan Tool.

To Access CC OBD readout:
* Car ignition on
* Press and hold the recirculation button
* Press and hold the up arrow button
* Release both buttons: "01c" will be displayed ("01c" indicates channel 1, "02c" indicates channel 2, etc.)


To select a different channel, press temperature + or temperature - buttons.

To call up information from a particular channel, select desired channel, and press the recirculation button.

To leave memory display, press the AUTO button, or switch the ignition off.
Diagnostic Channels and their descriptions
Channel Function
1 System malfunction - displayed as a Diagnostic Trouble Code (DTC)

2 Digital value of Interior Temperature Sensor in Headliner (G86)
3 Digital value of Interior Temperature Sensor in Instrument Panel (G56)
4 Digital value of Fresh Air Intake Duct Temperature Sensor (G89)
5 Digital value of Outside Air (Ambient) Temperature Sensor, front (G17)
6 Digital value of Outside Air (Ambient) Temperature Sensor
7 Digital value of Ambient Temperature Sensor at Fresh Air Blower (G109)
8 Digital value of Temperature Regulator Flap Motor Position Sensor (G92)
9 Delta value of Temperature Regulator Flap
10 Non-corrected specified value of Temperature Regulator Flap
11 Digital value of Central Flap Motor Position Sensor (G112)
12 Specified value for Central Flap
13 Digital value of Footwell/Defroster Flap Motor Position Sensor (G114)
14 Specified value of Footwell/Defroster Flap
15 Digital value of Back Pressure Flap Motor Position Sensor (G113) (Not installed in US/Canada models)
16 Specified value of Back Pressure Flap
17 Vehicle Speed (km/h)
18 Actual Fresh 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 (F118)
23 Cyclings of the A/C Refrigerant High Pressure Switch (F118)
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 (Should equal Engine Speed x 1.28)
30 Software version
31 Display check (all segments of A/C Control Head display light up)
32 Position Sensor malfunction counter, Temperature Regulator Flap
33 Position Sensor malfunction counter, Central Flap
34 Position Sensor malfunction counter, Footwell/Defroster Flap
35 Position Sensor malfunction counter, Air Flow Flap
36 Feedback value, cold end-stop, Temperature Regulator Flap Motor Position Sensor (G92)
37 Feedback value, hot end-stop (maximum stop), Temperature Regulator Flap Motor Position Sensor (G92)
38 Feedback value, cold end-stop, Central Flap Motor Position Sensor (G112)
39 Feedback value, hot end-stop, Central Flap Motor Position Sensor (G112)
40 Feedback value, cold end-stop, Footwell/Defroster Flap Motor Position Sensor (G114)
41 Feedback value, hot end-stop, Footwell/Defroster Flap Motor Position Sensor (G114)
42 Feedback value, cold end-stop, Back Pressure Flap Motor Position Sensor (G113) (Not installed in US/Canada models)
43 Feedback value, hot end-stop, Back Pressure Flap Motor Position Sensor (G113) (Not installed in US/Canada models)
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 °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 °C
52 Graphics channel 1, see chart below. NOTE: When Diagnostic Channel 52
is selected, .--.-. is displayed first. A/C compressor switch-off conditions
are then identified by illuminated segments of the .88.8. display.
53 Graphics channel 2, see chart below. NOTE: When Diagnostic Channel 53
is selected, .--.-. is displayed first. A/C system electrical outputs are
then identified by illuminated segments of the .88.8. display.
54 Control characteristics
55 Outside (ambient) temperature, in Celsius or Fahrenheit depending on the setting
of the A/C control head
56 Temperature in Celsius, from Interior Temperature Sensor in Headliner (G86)
57 Temperature in Celsius, from Interior Temperature Sensor in Instrument Panel (G56)
58 Temperature in Celsius, from Fresh Air Intake Duct Temperature Sensor (G89)
59 Temperature in Celsius, from Outside Air (Ambient) Temperature Sensor, front (G17)
60 Temperature in Celsius, from Ambient Temperature Sensor at Fresh Air Blower (G109)
61 Software version (latest)



Diagnostic Trouble Codes

DTC Malfunction Remarks
________________________________________
00.0 No Malfunction Present
________________________________________
02.1 Interior Temperature Sensor in Headliner (G86), static open Digital default value of 128 is used if sensor fails
02.2 Interior Temperature Sensor in Headliner (G86), static short
02.3 Interior Temperature Sensor in Headliner (G86), sporadic open
02.4 Interior Temperature Sensor in Headliner (G86), sporadic short
________________________________________
03.1 Interior Temperature Sensor in Instrument Panel (G56), static open Digital default value of 128 is used if sensor fails
03.2 Interior Temperature Sensor in Instrument Panel (G56), static short
03.3 Interior Temperature Sensor in Instrument Panel (G56), sporadic open
03.4 Interior Temperature Sensor, in Instrument Panel (G56), sporadic short
________________________________________
04.1 Fresh Air Intake Duct Temperature Sensor (G89), static open Value supplied by outside air temperature sensor (G17) is used if sensor fails
04.2 Fresh Air Intake Duct Temperature Sensor (G89), static short
04.3 Fresh Air Intake Duct Temperature Sensor (G89), sporadic open
04.4 Fresh Air Intake Duct Temperature Sensor (G89), sporadic short
________________________________________
05.1 Outside Air (Ambient) Temperature Sensor (G17), front, static open Value supplied by fresh air intake duct temperature sensor (G89) is used if sensor fails

Digital default value of 128 is used if sensors (G89) and (G17) both fail
05.2 Outside Air (Ambient) Temperature Sensor (G17), front, static short
05.3 Outside Air (Ambient) Temperature Sensor (G17), front, sporadic open
05.4 Outside Air (Ambient) Temperature Sensor (G17), front, sporadic short
________________________________________
06.1 Engine Coolant Temperature (ECT) (G110), static open Engine coolant temperature is calculated if sensor should fail or is not installed; diagnosis occurs only above 0°C (32°F)
06.2 Engine Coolant Temperature (ECT) (G110), static short
06.3 Engine Coolant Temperature (ECT) (G110), sporadic open
06.4 Engine Coolant Temperature (ECT) (G110), sporadic short
________________________________________
07.1 Ambient Temperature Sensor at Fresh Air Blower (G109), static open Programmed corrective value = 0
07.2 Ambient Temperature Sensor at Fresh Air Blower (G109), static short
07.3 Ambient Temperature Sensor at Fresh Air Blower (G109), sporadic open
07.4 Ambient Temperature Sensor at Fresh Air Blower (G109), sporadic short
________________________________________
08.1 Temperature Regulator Flap Motor Position Sensor (G92), static open 08.1 - 08.4: Temperature regulator flap motor will no longer be controlled automatically; manual adjustment only.
08.2 Temperature Regulator Flap Motor Position Sensor (G92), static short
08.3 Temperature Regulator Flap Motor Position Sensor (G92), sporadic open
08.4 Temperature Regulator Flap Motor Position Sensor (G92), sporadic short
08.5 Temperature Regulator Flap, static block 08.5 - 08.7: Motor is cycled; software attempts to eliminate block. Watch Diagnostic Channel 8 to see digital value for flap motor position sensor (G92).
08.6 Temperature Regulator Flap Motor Position Sensor (G92), malfunction
08.7 Temperature Regulator Flap, sporadic block
________________________________________
11.1 Central Flap Motor Position Sensor (G112), static open 11.1 - 11.4 Central flap motor will no longer be controlled automatically; manual adjustment only.
11.2 Central Flap Motor Position Sensor (G112), static short
11.3 Central Flap Motor Position Sensor (G112), sporadic open
11.4 Central Flap Motor Position Sensor (G112), sporadic short
11.5 Central Flap, static block 11.5 - 11.7 Motor is cycled; software attempts to eliminate block. Watch Diagnostic Channel 11 to see digital value for central flap motor position sensor (G112).
11.6 Central Flap Motor Position Sensor (G112), malfunction
11.7 Central Flap, sporadic block
________________________________________
13.1 Footwell/Defroster Flap Motor Position Sensor (G114), static open 13.1 - 13.4 Footwell/Defroster flap motor will no longer be controlled automatically; manual adjustment only.
13.2 Footwell/Defroster Flap Motor Position Sensor (G114), static short
13.3 Footwell/Defroster Flap Motor Position Sensor (G114), sporadic open
13.4 Footwell/Defroster Flap Motor Position Sensor (G114), sporadic short
13.5 Footwell/Defroster Flap, static block 13.5 - 13.7 Motor is cycled; software attempts to eliminate block. Watch Diagnostic Channel 13 to see digital value for footwell/defroster flap position sensor (G114).
13.6 Footwell/Defroster Flap Motor Position Sensor (G114), malfunction
13.7 Footwell/Defroster Flap, sporadic block
________________________________________
15.1 Back Pressure Flap Motor Position sensor (G113), static open 15.1 - 15.4 Digital value internally programmed for limp-home mode
15.2 Back Pressure Flap Motor Position Sensor (G113), static short
15.3 Back Pressure Flap Motor Position Sensor (G113), sporadic open
15.4 Back Pressure Flap Motor Position Sensor (G113), sporadic short
15.5 Back Pressure Flap, static block 15.5 - 15.7 Motor is cycled; software attempts to eliminate block. Watch Diagnostic Channel 15 to see digital value for back pressure flap position sensor (G113).
15.6 Back Pressure Motor Position Sensor (G113), malfunction
15.7 Back Pressure Flap, sporadic block
________________________________________
17.0 Vehicle Speed Signal faulty
________________________________________
18.1 Fresh Air Blower voltage, static
18.3 Fresh Air Blower voltage, sporadic
________________________________________
20.1 A/C compressor voltage not OK - static Compressor remains off until voltage is greater than 10.8V for at least 25 seconds
20.3 A/C compressor voltage not OK - sporadic
________________________________________
22.1 A/C Refrigerant High Pressure Switch (F118), static open Compressor remains off until switch closes
22.3 A/C Refrigerant High Pressure Switch (F118), sporadic open
22.5 A/C Refrigerant High Pressure Switch (F118), 120X open Compressor re-engagement circuit, VAG1551 Scan Tool function
________________________________________
29.1 Belt slip detection "soft," static
29.2 Belt slip detection "hard," static
29.3 Belt slip detection "soft," sporadic
29.4 Belt slip detection "hard," sporadic




Diagnostic Channel 52 - Graphics Channel 1

A/C Compressor switch-off conditions
Note: if an A/C compressor switch-off condition exists, a segment of the .88.8. display, noted below as an alpha-numeric code, will illuminate.





Segment Condition
A1 Slippage or blockage, A/C Refrigerant High Pressure Switch, 120x off
B1 Engine Speed (RPM) less than 200 - 500
C1 Engine Speed (RPM) greater than 6000
D1 Engine Speed (RPM) greater than 6000
E1 System function OK*
F1 System function OK*
G1 System function OK*
A2 A/C manually switched off (A/C standby canceled)
B2 Low Voltage
C2 Kick-down switch (via Transmission Control Module (TCM), compressor off for 12 seconds max.
E2 A/C Refrigerant Low Pressure Switch (F73)
F2 A/C Refrigerant High Pressure Switch (F118)
G2 System function OK*
A3 ECON mode selected
B3 OFF selected
C3 Outside (ambient) temperature too low
D3 Engine management system (compressor will remain off for 3 -12 seconds)
E3 High pressure occurrences more than 30 times
F3 Ambient Temperature Sensor at Fresh Air Blower (G109) less than 27°F (-3°C)
G3 System function OK*
Decimal Point Visible: A/C compressor ON
Not Visible: A/C compressor OFF
*segments g1, g2, and g3 must illuminate simultaneously to indicate system function is OK.



Diagnostic Channel 53 - Graphics Channel 2

Active electrical outputs
Note: When a NO system electrical output is activated, a segment of the .88.8. display, noted below as an alpha-numeric code, will illuminate. The decimal point in the .88.8. display will not illuminate in this channel.



Segment Condition
A1 Fan for interior temperature sensor
B1 Fresh air/recirculation flap closed (recirculation mode)
C1 Heater valve closed
D1 Bi-directional wiring harness
E1 A/C compressor ON
F1 coolant fan first speed ON
G1 System function OK*
A2 Air flow flap open
B2 Air flow flap open
C2 Air flow flap closed
D2 Footwell/Defroster flap in footwell position
E2 Footwell/Defroster flap in footwell position
F2 Footwell/Defroster flap in defroster position
G2 System function OK*
A3 Central flap in instrument panel outlet position
B3 Central flap in instrument panel outlet position
C3 Central flap in footwell outlet/defrost position
D3 Temperature flap in cold air position
E3 Temperature flap in cold air position
F3 Temperature flap in warm air position
G3 System function OK*


* Segments g1, g2, and g3 must illuminate simultaneously to indicate system function is OK

gietl

hopefully the little control arm thing just popped off. It's not to bad to put back on. Easier than having to replace a flapper.