BMW DTC P249B – EGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic (Bank 2)
DTC P249B meaning on BMW
DTC P249B on a BMW indicates an issue with the EGR (Exhaust Gas Recirculation) Cooler Bypass Position Sensor Circuit on Bank 2. This fault code signifies that the position sensor circuit for the EGR cooler bypass valve is experiencing intermittent or erratic behavior.
BMW DTC P249B symptoms
Symptoms of DTC P249B on a BMW may include:
- Check Engine Light (MIL) illuminated
- Reduced engine performance
- Increased fuel consumption
- Engine stalling or rough idling
BMW DTC P249B causes
Common causes of DTC P249B on a BMW include:
- Faulty EGR cooler bypass position sensor
- Wiring or connector issues in the sensor circuit
- Carbon buildup in the EGR system
- Software or calibration issues
BMW DTC P249B seriousness
DTC P249B should not be ignored as it can lead to reduced engine efficiency and potential drivability issues. While the vehicle may still be operable, continued driving with this fault unresolved can cause further damage to the engine or emissions system.
How to diagnose DTC P249B on BMW
To diagnose DTC P249B on a BMW, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault code and freeze frame data
- Inspect the EGR cooler bypass position sensor and its wiring for any visible damage
- Test the sensor’s resistance and voltage output
- Check for carbon buildup in the EGR system
- Perform a software update or calibration if necessary
How to fix DTC P249B on BMW
To fix DTC P249B on a BMW, the following steps may be taken:
- Replace the faulty EGR cooler bypass position sensor
- Repair or replace any damaged wiring or connectors in the sensor circuit
- Clean out any carbon deposits in the EGR system
- Perform a software update or calibration as needed
How to erase DTC P249B on BMW
To erase DTC P249B on a BMW, the fault code can be cleared using a diagnostic scanner. After the necessary repairs have been made, the code can be reset, and the Check Engine Light should turn off. It is important to ensure that the underlying issue causing the fault code has been addressed before clearing it.
Recommended tools & DTC Scanners for BMW
Best Diagnostic App for modern BMWs: BimmerLink
Recommended Bluetooth adapter for Bimmerlink: OBDLink CX
Cable adapter for Bimmerlink: Enet Cable USB Type C
For older BMWs we recommend: Autel AutoLink AL319 (2024 version)
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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