| 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) |
Diagnostic Trouble Code Meanings
| Diagnostic Trouble
Code (Sensor) |
Malfunction Description |
| 00.0 | No malfunction present |
| 02.1 (G86) | Interior Temperature Sensor, in Headliner, static open, *02.1 (see below) |
| 02.2 | Interior Temperature Sensor, in Headliner, static short, see 02.1 |
| 02.3 | Interior Temperature Sensor, in Headliner, sporadic open |
| 02.4 | Interior Temperature Sensor, in Headliner, sporadic short |
| 03.1 (G56) | Interior Temperature Sensor, in Instrument Panel, static open, see 02.1 |
| 03.2 | Interior Temperature Sensor, in Instrument Panel, static short, see 02.1 |
| 03.3 | Interior Temperature Sensor, in Instrument Panel, sporadic open |
| 03.4 | Interior Temperature Sensor, in Instrument Panel, sporadic short |
| 04.1 (G89) | Fresh Air Intake Duct Temperature Sensor, static open, *04.1 (see below) |
| 04.2 | Fresh Air Intake Duct Temperature Sensor, static short, see 04.1 |
| 04.3 | Fresh Air Intake Duct Temperature Sensor, sporadic open |
| 04.4 | Fresh Air Intake Duct Temperature Sensor, sporadic short |
| 05.1 (G17) | Outside Air (Ambient) Temperature Sensor, front, static open, *05.1 (see below) |
| 05.2 | Outside Air (Ambient) Temperature Sensor, front, static short, see 05.1, *05.2 (see below) |
| 05.3 | Outside Air (Ambient) Temperature Sensor, front, sporadic open |
| 05.4 | Outside Air (Ambient) Temperature Sensor, front, sporadic short |
| 06.1 (G110) | Engine Coolant Temperature (ECT), A/C static open, *06.1 (see below) |
| 06.2 | Engine Coolant Temperature (ECT), A/C static short, see 06.1 |
| 06.3 | Engine Coolant Temperature (ECT), A/C sporadic open |
| 06.4 | Engine Coolant Temperature (ECT), A/C sporadic short |
| 07.1 (G109) | Ambient Temperature Sensor at Fresh Air Blower, static open, *07.1 (see below) |
| 07.2 | Ambient Temperature Sensor at Fresh Air Blower, static short, see 07.1 |
| 07.3 | Ambient Temperature Sensor at Fresh Air Blower, sporadic open |
| 07.4 | Ambient Temperature Sensor at Fresh Air Blower, sporadic short |
| 08.1 (G92) | Temperature Regulator Flap Motor Potentiometer, static open, *08.1 (see below) |
| 08.2 | Temperature Regulator Flap Motor Potentiometer, static short, see 08.1 |
| 08.3 | Temperature Regulator Flap Motor Potentiometer, sporadic open |
| 08.4 | Temperature Regulator Flap Motor Potentiometer, sporadic short |
| 08.5 | Temperature Regulator Flap, static block, *08.5 (see below) |
| 08.6 | Temperature Regulator Flap Motor Potentiometer, malfunction |
| 08.7 | Temperature Regulator Flap, sporadic block |
| 11.1 (G112) | Central Flap Motor Potentiometer, static open, *11.1 (see below) |
| 11.2 | Central Flap Motor Potentiometer, static short, see 11.1 |
| 11.3 | Central Flap Motor Potentiometer, sporadic open |
| 11.4 | Central Flap Motor Potentiometer, sporadic short |
| 11.5 | Central Flap, static block, *11.5 (see below) |
| 11.6 | Central Flap Motor Potentiometer, malfunction |
| 11.7 | Central Flap, sporadic block |
| 13.1 (G114) | Footwell/Defroster Flap Motor Potentiometer, static open, *13.1 (see below) |
| 13.2 | Footwell/Defroster Flap Motor Potentiometer, static short, see 13.1 |
| 13.3 | Footwell/Defroster Flap Motor Potentiometer, sporadic open |
| 13.4 | Footwell/Defroster Flap Motor Potentiometer, sporadic short |
| 13.5 | Footwell/Defroster Flap, static block, *13.5 (see below) |
| 13.6 | Footwell/Defroster Flap Motor Potentiometer, malfunction |
| 13.7 | Footwell/Defroster Flap, sporadic block |
| 15.1 (G113) | Air Flow Flap Motor Potentiometer, static open, *15.1 (see below) |
| 15.2 | Air Flow Flap Motor Potentiometer, static short, see 15.1 |
| 15.3 | Air Flow Flap Motor Potentiometer, sporadic open |
| 15.4 | Air Flow Flap Motor Potentiometer, sporadic short |
| 15.5 | Air Flow Flap, static block, see *15.5 (see below) |
| 15.6 | Air Flow Flap Motor Potentiometer, malfunction |
| 15.7 | Air Flow 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, *20.1 (see below) |
| 20.3 | A/C compressor voltage not OK - sporadic |
| 22.1 (F118) | A/C Refrigerant High Pressure Switch, static open, *22.1 (see below) |
| 22.3 | A/C Refrigerant High Pressure Switch, sporadic open |
| 22.5 | A/C Refrigerant High Pressure Switch, 120X open, *22.5 (see below) |
| 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 Trouble Code Notes:
| *02.1 | Digital default value of 128 is programmed if sensor fails |
| *04.1 | Value supplied by Temp. Sensor is used if sensor fails |
| *05.1 | Value supplied by Temp. Sensor is used if sensor fails |
| *05.2 | Digital default value of 128 is programmed if sensors G89 & G17 both fail |
| *06.1 | Engine Coolant Temperature is calculated is sensor should fail or is not installed; diagnosis occurs only above 0 degrees Celsius |
| *07.1 | Programmed corrective value = 0 |
| *08.1 | Temperature Regulator Flap Motor will no longer be controlled automatically; manual adjustment only |
| *08.5 | Motor is cycled; software attempts to eliminate block |
| *11.1 | Central Flap Motor will no longer be controlled automatically; manual adjustment only |
| *11.5 | Motor is cycled; software attempts to eliminate block |
| *13.1 | Footwell/Defroster Flap Motor will no longer be controlled automatically; manual adjustment only |
| *13.5 | Motor is cycled; software attempts to eliminate block |
| *15.1 | Digital value is internally programmed for limp-home mode |
| *15.5 | Motor is cycled; software attempts to eliminate block |
| *20.1 | Compressor remains off until voltage is greater than 10.8V for at least 25 seconds |
| *22.1 | Compressor remains off until switch closes |
| *22.5 | Compressor re-engagement circuit, VAG 1551 Scan Tool function |
OBD Channel 52 - A/C Compressor switch-off codes
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 |
a2 |
A/C manually switched off (A/C standby canceled) |
b2 |
low voltage |
c2 |
Kick-down switch, compressor off for 12secs max. |
d2 |
Engine Coolant Temperature (ECT) warning light switched |
e2 |
A/C Refrigerant Low Pressure Switch (F73) |
f2 |
A/C Refrigerant High Pressure Switch (F118) |
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 degF (-3 degC) |
g1,g2,g3 |
System function OK (g1+g2+g3 must illuminate simultaneously to indicate system is OK) |
Decimal Point Lit |
A/C compressor ON |
Decimal Point Unlit |
A/C compressor OFF |
OBD Channel 53 - Climate system electrical output codes
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 |
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 |
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 |
g1,g2,g3 |
System function OK (g1+g2+g3 must illuminate simultaneously to indicate system is OK) |
Written by: Mark Quinn
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