Remarks on requests from Air Quality Sensor G238 in zone "3" of display group " 014"

WARNING: This page is about a different car, the 2008 Audi S4, 2008 Audi RS 4, and 2008 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

Air Quality Sensor G238 request code		Meaning
5 (or 7)		No increased air pollution values measured No request for autom. recirculated-air mode, fresh-air mode The display "5" or "7" depends on the version of the operating and display module, Climatronic Control Module J255
1		Slight increase in oxidizable gases in the air Fresh-air or autom. recirculated-air mode depending on various conditions (refer to display zone "4")
2		Considerable increase in oxidizable gases in the air Fresh-air or autom. recirculated-air mode depending on various conditions (refer to display zone "4")
3		Slight increase in reducible gases in the air Fresh-air or autom. recirculated-air mode depending on various conditions (refer to display zone "4")
4		Considerable increase in reducible gases in the air Fresh-air or autom. recirculated-air mode depending on various conditions (refer to display zone "4")
0, 254 or 255		No signal from Air Quality Sensor G238 Open circuit in power supply or Ground (GND) connection to Air Quality Sensor G238 Open circuit or short to Ground (GND)/positive in wiring between and operating and display module, Climatronic Control Module J255 and Air Quality Sensor G238 Air Quality Sensor G238 defective Replace Air Quality Sensor G238

NOTE:

Oxidizable gases include carbon monoxide, benzene and hexane. These react with the oxygen in the air and are found, for example, in gasoline engine exhaust gases.
Reducible gases include nitrogen oxides, sulphur dioxides and hydrogen sulphides. These react with other substances, give off oxygen in the process and are found, for example, in engine exhaust gases.
Depending on the hardware/software version of the operating and display module, Climatronic Control Module J255, there is either no display for vehicles with no Air Quality Sensor G238 or the display is "n. installed".