Air Mass Sensor Fault – Mercedes W222
System: Engine Management
Component: Air Mass Sensor (MAF)
Part Reference: A642 090 17 42
Model: Mercedes S-Class W222
Fault Codes
• P00AA00 – Intake air temperature sensor 1 electrical fault
• P011303 – Intake air temperature sensor 1 short circuit to positive
• P0404FD – EGR control fault
• P010085 – Air mass sensor signal implausible
• P010A00 – Mass air flow sensor signal fault
• P011029 – Intake air temperature signal fault
Typical Symptoms
• Engine warning light illuminated
• Reduced engine performance
• Incorrect air-fuel mixture
• Possible EGR or intake-related fault messages
Possible Cause
• Faulty air mass sensor
• Integrated intake air temperature sensor failure
• Sensor signal implausible
• Wiring or connector issue
Component Location :The air mass sensors are located in the intake air ducts on both sides of the engine.
Diagnostic Insight
Multiple fault codes relating to air mass and intake air temperature signals may indicate a fault with the air mass sensor.
The intake air temperature sensor is often integrated within the air mass sensor, which can trigger multiple related fault codes.
Technicians usually check:
• live data from both air mass sensors
• signal comparison between left and right banks
• wiring and connector condition
In this case, testing showed that although the issue appeared on one side, the opposite air mass sensor was faulty.
Replacement of the air mass sensor A642 090 17 42 resolved the fault and cleared the engine warning light.
Important Note
On engines with two air mass sensors, faults may not always indicate the correct side.
Signal comparison between both sensors is required for accurate diagnosis.
⚠ Professional Diagnostic Recommended
Modern Mercedes-Benz emissions systems require specialist diagnostic equipment. The vehicle should be inspected by a Mercedes-Benz dealer or qualified Mercedes specialist.
