What it means
A control module has stopped receiving expected network messages from the EGR cooler bypass position sensor on bank 1. The effect on EGR cooler 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 EGR cooler bypass position sensor reports the bypass position for bank 1, allowing the control system to manage exhaust-gas cooling on that bank. This code sets when a module stops receiving the sensor's expected network messages, which can interfere with EGR cooler control.
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
- EGR cooler operation may be affected
How to diagnose it
- Record freeze-frame data and scan all modules for related EGR or communication codes to see when bank 1 sensor messages were lost.
- Use live data to check whether the EGR cooler bypass position for bank 1 is reported and changes as commanded.
- Inspect the bank 1 bypass position sensor connector and network wiring for looseness, corrosion, heat damage, or chafing.
- Check the sensor or associated module's power and ground according to the manufacturer's wiring information.
- Test the network circuit to the bank 1 sensor for opens or shorts, then evaluate the sensor or module if the wiring and feeds pass.
Common fixes
- Reconnect or clean the bank 1 bypass position sensor connector.
- Repair damaged network wiring or connector terminals serving the bank 1 sensor.
- Restore the sensor module's power or ground.
- Replace the bank 1 bypass position sensor or its module if the circuits test correctly and messages remain absent.
Can I keep driving?
You may be able to drive if the engine runs normally, but avoid heavy loads or towing if a warning or loss of power appears. Continued EGR cooler control problems can increase emissions and may affect engine operation.
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.