AQS(Air Quality System) keeps air inside in the most suitable state for driver. In polluted area AQS detects hazardous gas and intercepts inflow automatically, Inversely, In fresh area it allows the inflow of air to prevent the shortage of air and the accumulation of carbon dioxide. AQS sensor is located at front side of condensor and once hazardous gas is detected, it delivers the voltage signal to ECU for closing intake door.
Air conditioner Control Module sets DTC B1258 if Feedback signal of AQS sensor has been detected below 0.1V for 0.3 seconds.
Item
Detecting Condition
DTC Strategy
Voltage check
Poor Connection in Harness
Short in circuit
Faulty AQS
Faulty Air conditioner Control Module
Enable Conditions
IG KEY ON
Threshold value
Feedback signal of AQS sensor has been detected below 0.1V for 0.3 seconds.
Failsafe
AQS function OFF
Operating condition
Voltage
Note
Right after IGN "ON"
2.5V ± 0.3V
Stay at Pre-Position
normal
4.3V ± 0.3V
Intake door : REC
Gas detected
0.9V ± 0.3V
Intake door : FRE
Preheating Time : (35 ± 2 sec.)