P009A MERCEDES-BENZ - Intake Air Temperature/Ambient Air Temperature Correlation
Faulty Intake Air Temperature (IAT) or Ambient Air Temperature (AAT) sensor
Biased IAT or AAT sensor
Engine Light ON (or Service Engine Soon Warning Light)
P009a Mercedes-benz Description
The P009A code indicates that the Intake Air Temperature
(IAT) and Ambient Air Temperature (AAT) sensor readings differ by more than a calibrated value.