Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Air Quality Sensor (Electronic Climate Control Only, Option)
The air quality sensor is available as an option for the electronic climate control from model year 2000. Its function is to transmit a signal to the climate control module (CCM) if it detects increased concentrations of pollutants in the outside air.
The air quality sensor measures the COx and NOx content.
The air quality sensor compares current values with previous ones and can calculate changes in pollutant concentrations.
The signal from the air quality sensor to the climate control module (CCM) is a pulse width modulation (PWM) signal and has four stages, 0-3:
- signal 0= no increase in or reduced pollutant level
- signal 1=gradual increase in pollutant level
- signal 2=moderate increase in pollutant level
- signal 3=rapid increase in pollutant level.
The control module uses the signal to control the recirculation damper motor.
The air quality sensor is located on the right-hand side of the fresh air intake under the cowl.
There are diagnostics for the air quality sensor.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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