Climate Control Exhaust Gas Sensor: Service and Repair

Air Quality Sensor G238, Removing And Installing







NOTE:
- The Air Quality Sensor G238 is a highly sensitive electronic component which could be destroyed by direct exposure to solvents, fuels and certain chemical compounds (contamination can ingress by way of area - A - for example with version "2" ).
- Never install an Air Quality Sensor G238 which has not been kept clean.
- After removal, do not set down Air Quality Sensor G238 in areas where it could come into contact with solvents, fuels or certain chemical compounds (liquids or vapors).
- There are different versions of the Air Quality Sensor G238. At the start of production, Air Quality Sensor G238 version "1" was installed. This sensor is gradually being replaced by version "2", however the mode of operation is identical.

Removing and installing
- Remove plenum chamber cover.

Version "1"







- Disconnect connector - A - from Air Quality Sensor G238.
- Remove bolt - B - and remove Air Quality Sensor G238.







Terminal assignment in connector - A -
1. B+ (terminal "15" )
2. Negative (terminal "31" )
3. Signal wire to operating and display module, Climatronic Control Module J255 (square-wave signal cannot be measured)
4. Not used

Version "2"







- Disconnect connector - A - from Air Quality Sensor G238.
- Release catch - B - and slide Air Quality Sensor G238 - C - downwards.

Terminal assignment in connector - A -
1. B+ (terminal "15" )
2. Negative (terminal "31")
3. Signal wire to operating and display module, Climatronic Control Module J255 (square-wave signal cannot be measured)