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Climate Control Exhaust Gas Sensor: Testing and Inspection

A.Q.S (AIR QUALITY SENSOR)

INSPECTION
1. Ignition "ON"
2. Using the scan tool.




3. Check the output voltage of AQS between terminals 2 and 3.

4. AQS diagnosis and fail safe.
Detect the open of signal for 7 seconds without choosing the AQS switch when IG on.
If 2.5V or more is detected for 3.5 seconds or more among 7 seconds, be judged the open of AQS signal. Operate as below fail safe function, while choosing AQS.
Fail safe: Release the AQS (AQS cannot be selected), Fresh/recirculation maintains previous situation of AQS selection.

NOTE: When IG is turned ON, AQS heats for 34 ± 5 seconds, it will output below 1.0 voltage during this time.