What it means
A control module has stopped receiving expected network messages from the diesel intake air flow B position sensor. The effect on intake air control depends on the vehicle's system design.
At a glance
- Usually lights the warning light of the system that lost communication
- Affects emissions; the car can fail an emissions test
How it works
The diesel intake air flow B position sensor reports the position of an intake-air control component. This code sets when a module stops receiving the expected network messages from sensor B, so the control system loses feedback from the B sensor specifically.
Common causes
Most likely first.
- Bus wiring open or shorted
- Module without power or ground
- Module failed
Symptoms
- Warning light or message related to the affected system
- Engine performance may be affected
How to diagnose it
- Record freeze-frame data and scan all modules for intake-air and communication codes to identify when sensor B messages stopped.
- Check live data specifically for the diesel intake air flow B position reading and whether it changes with an intake-control command.
- Inspect sensor B's connector and network wiring for corrosion, loose pins, chafing, or heat and vibration damage.
- Check power and ground at sensor B or its associated module using the manufacturer's wiring information.
- Test the network circuit to sensor B for opens or shorts, then assess the sensor or module if wiring and electrical feeds pass.
Common fixes
- Reconnect or clean the intake air flow B position sensor connector.
- Repair damaged network wiring or connector terminals serving sensor B.
- Restore the sensor module's power or ground.
- Replace sensor B or its associated module if wiring and feeds pass but communication remains lost.
Can I keep driving?
A short, gentle drive may be possible if the engine runs normally, but avoid towing or hard acceleration if power is reduced. Missing intake-position feedback can worsen drivability and emissions.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.