Climate Control Exhaust Gas Sensor: Service and Repair

Air Quality Sensor (G238) with Humidity Sensor In Fresh Air Intake Duct (G657)

Depending on the equipment, the air quality sensor - 1 - is available individually or together with the humidity sensor in fresh air intake duct - 3 - in one shared housing - 2 -. Allocation, refer to Electronic Parts Catalog (ETKA).






• In the Basic version of the A/C system, only the humidity sensor in fresh air intake duct is installed.

• In the Comfort version of the A/C system, an air quality sensor is integrated in the housing in addition to the humidity sensor in fresh air intake duct.

Removal






- Remove the plenum chamber cover.

- Release the securing tab - 1 - - arrow A - and turn housing - 3 - for air quality sensor/humidity sensor in fresh air intake duct counterclockwise - arrow B -.

- Remove the housing from the fresh air intake grille - 4 -.

- Disconnect the electrical connector - 2 -.

• Do not store a removed air quality sensor with a humidity sensor in fresh air intake duct (G657) in areas that are contaminated with solvents, fuels and certain chemical compounds (fluids or gases).

Installation






Installation is done is reverse order, observe the following:

• To prevent water from entering the A/C unit via the intake duct - 4 - when the plenum chamber cover - 1 - is installed, the cowl panel trim - 2 - and the plenum chamber cover with the cover frame - 5 - for the intake duct must not be damaged.

• The cowl panel trim of the plenum chamber cover must be completely engaged in the frame - 3 - of the windshield.

• The plenum chamber cover must be correctly and completely inserted in the mount - arrow - of the cowl panel trim.

- Install the plenum chamber cover.