Ambient temperature sensor, AAT2 Plaus Low
â–¶ How to fix
Compare the temperature between the ambient temperature sensors (AAT1, AAT2 and T202/T126) Check the wiring and the connectors to the ambient temperature sensor (AAT2) Change the ambient temperature sensor (AAT2) To verify the repair run the vehicle above 30km/h for 2 minutes.
What you'll see
No driver-visible symptom recorded.
System reaction
The system may shut off the EGR system at low measure ambient temperatures.
Diagnostic depth
Detection
The ambient temperature is lower compared to the other ambient temperature sensor (AAT1) and to the temperature sensor in the air inlet (T202 or T126).
Possible cause
The ambient temperature sensor (AAT2) is faulty ot the sensor has been exposed to unusually low temperature compared with the other temperature sensors.