CO2 (Oxygen) sensor malfunction
Thread Starter
Junior Member
Joined: Nov 2021
Posts: 45
Likes: 15
CLS350D
CO2 (Oxygen) sensor malfunction
This morning when I opened door, immediately red message popup on the screen "Air condition not working, open windows to ensure fresh air and visit repair shop".
First i thought AC Compressor is dead, then I took car to service shop and they told me it is "CO2 Sensor" which is only $40 but difficult to reach and it requires to leave car for 2 days to dismantle everything inside.
I ordered sensor and came back home, shut down car, turn it on after 1 hour and no more message, AC works fine.
Anyone had issue with this sensor, should i still replace it or you think it was some kind of temporarily dummy miss function?
First i thought AC Compressor is dead, then I took car to service shop and they told me it is "CO2 Sensor" which is only $40 but difficult to reach and it requires to leave car for 2 days to dismantle everything inside.
I ordered sensor and came back home, shut down car, turn it on after 1 hour and no more message, AC works fine.
Anyone had issue with this sensor, should i still replace it or you think it was some kind of temporarily dummy miss function?
Senior Member
Joined: Jul 2023
Posts: 296
Likes: 91
S550 V8, CL600 V12, SLK32 AMG
Personally. I would wait to see if it happens again and keep the sensor.
At best it was just a fluke, at worst, you have to get the car fixed anyway.
O2 sensor is emissions, so has to get fixed, but I doubt it will leave you stranded.
At best it was just a fluke, at worst, you have to get the car fixed anyway.
O2 sensor is emissions, so has to get fixed, but I doubt it will leave you stranded.
Last edited by waterzap99; Oct 24, 2023 at 09:26 AM.
Super Member
Joined: Dec 2013
Posts: 522
Likes: 69
From: North Texas
Presently 19 S560 SEDAN, 2014 XK, SOLD GLE 450e
Does not Mercedes use carbon dioxide as a refrigerant and there is a dedicated carbon dioxide sensor INSIDE the car to detect a failed/open line/component...............vs the Oxygen sensors (O2) in the tail pipes ? My thoughts is that this failed sensor would be inside the car.
The mind strays thinking the carbon dioxide might have all leaked out and that is why you do not have the fault.........but on the other hand if the a/c is working.....ignore this post.
The mind strays thinking the carbon dioxide might have all leaked out and that is why you do not have the fault.........but on the other hand if the a/c is working.....ignore this post.
Last edited by HAILERS2; Oct 26, 2023 at 06:01 PM.
