how to replace air quality sensor (G238 : 5K0907659) Tiguan 2017 : 263425 - Air Quality Sensor B10AF 04 [008] - Internal System Fault

2017 Mk2 Tiguan 150TDI 4Motion , yellow DTC light on

Fault code was

263425 - Air Quality Sensor
          B10AF 04 [008] - Internal System Fault
          Intermittent - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 3
                    Reset counter: 243
                    Mileage: 77120 km
                    Date: 2022.08.28
                    Time: 10:16:46

                    Outside temperature: 19.0 °C
                    Voltage terminal 30: 14.3 V
                    System run time-Engine running time: 253 s
                    System run time-Terminal 15 on: 253 s
                    Air quality status: Malfunction
                    System run time-Engine running time: 253 s
                    System run time-Terminal 15 on: 253 s

threads that helped

https://forums.ross-tech.com/index.php?threads/29183/

https://forums.ross-tech.com/index.php?threads/25677/

non critical role, you can still drive the car 

• Sensor for air quality detects pollutants in the ambient air (mostly gasoline and/or diesel fumes).
• The Climatronic Control Module -J255- evaluates the signal from the Air Quality Sensor -G238-. The A/C system is activated depending on the strength and type of heavily polluted air.

This picture , 19 indicates the sensor G238

Note on my UK car this was incorrect, mine was on the passengers side (offside) for me

https://vwts.ru/articles/electro/vw-tiguan-2-fitting-locations.html#1.18

Air Quality Sensor -G238-, Removing and Installing is shown in the link below.

It also gives a comprehensive list of what the sensor does.

https://www.vwtiguan.org/874/additional_components_for_control_and_regulation.html

dont have access to TPS, so bought from autodoc £39 + 5 shipping, took 5 days

OEM Part number is 5K0907659 (superceeds 1K part number)

https://www.autodoc.co.uk/aic/16115754

PIC

Options also for other sensors for £48 (Hella) £63 (Herth and Buss) and £89 (Vemo) , time will tell if the AIC part is ok

(If i chose again Id probably go for the Hella part as it looks like the part I removed : https://www.autodoc.co.uk/hella/7915637 )

Replacement is easy.

• open bonnet
• sensor is on the RHS (for a uk car)
• remove 1 or more clips holding wiper arm back cover to car body on front edge
• lift up the black plastic cover  (enough so you can gain access , you dont need to remove it)
• remove black cover (optional) but its easy
• push tabs to allow removal of sensor from car body bracket
• disconnect connector from sensor
• replace (checking its a match for what you had before)  and reverse steps
• use vcds or other to scan and remove any fault codes