P123E – BMW DTC

BMW DTC P123E – NOx Sensor Signal Too Low (Bank 1)

DTC P123E meaning on BMW

DTC P123E on a BMW indicates that the NOx (Nitrogen Oxide) sensor signal for Bank 1 is too low. The NOx sensor is responsible for monitoring the levels of nitrogen oxide in the exhaust gases to ensure compliance with emissions regulations.

BMW DTC P123E symptoms

Symptoms of DTC P123E on a BMW may include:

• Check Engine Light illuminated
• Reduced engine performance
• Increased fuel consumption
• Possible exhaust odor

BMW DTC P123E causes

The common causes of DTC P123E on a BMW include:

• Failed NOx sensor
• Wiring or connector issues
• Exhaust system leaks
• Software or calibration issues

BMW DTC P123E seriousness

DTC P123E should not be ignored as it can lead to increased emissions, reduced fuel efficiency, and potential engine damage if left unresolved. It is important to address this issue promptly to maintain the vehicle’s performance and environmental compliance.

How to diagnose DTC P123E on BMW

To diagnose DTC P123E on a BMW, you can follow these steps:

1. Use a diagnostic scanner to retrieve the fault codes
2. Inspect the NOx sensor and its wiring for any visible damage
3. Check for exhaust leaks or other related issues
4. Perform a sensor test to verify its functionality

How to fix DTC P123E on BMW

To fix DTC P123E on a BMW, you may need to:

1. Replace the faulty NOx sensor
2. Repair any damaged wiring or connectors
3. Address any exhaust system leaks
4. Update software or perform calibration if necessary

How to erase DTC P123E on BMW

To erase DTC P123E on a BMW, you can:

1. Use a diagnostic scanner to clear the fault codes
2. Ensure that the underlying issue causing the fault code has been resolved
3. Perform a test drive to confirm that the code does not return

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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