What it means
A control module has stopped receiving expected network messages from the turbocharger/supercharger boost control A position sensor. The effect on boost control and engine performance 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
- The engine or gearbox may go into limp mode
How it works
The turbocharger or supercharger boost control A position sensor reports the position of a boost-control component. This code sets when a module stops receiving the expected network messages from sensor A, so boost control may lack position feedback and engine power may be limited.
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 boost-control and communication codes before clearing anything, noting any reduced-power events.
- Check live data for boost control A position and compare its reported value with commanded position during a safe operating test.
- Inspect the boost control A sensor connector and network wiring for loose pins, corrosion, chafing, or heat damage near the turbocharger or supercharger.
- Check power and ground at sensor A or its associated module according to the manufacturer's wiring information.
- Test the network circuit to sensor A for opens or shorts, then evaluate the sensor or module if wiring and feeds pass.
Common fixes
- Reconnect or clean the boost control A position sensor connector.
- Repair damaged or heat-affected network wiring and connector terminals.
- Restore the sensor module's power or ground.
- Replace the boost control A position sensor or associated module if circuit checks pass but communication does not return.
Can I keep driving?
Avoid hard acceleration, towing, and steep climbs because boost may be limited or unpredictable; stop if power loss makes the vehicle unsafe. Continued operation under load can worsen drivability and may stress the boost-control system.
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.