BMW DTC P118B – Engine Oil Separator Heating Circuit Low
DTC P118B meaning on BMW
The DTC P118B on a BMW refers to the Engine Oil Separator Heating Circuit Low. This diagnostic trouble code indicates that there is a low voltage condition detected in the heating circuit of the engine oil separator.
BMW DTC P118B symptoms
Some common symptoms associated with the BMW DTC P118B may include:
- Check Engine Light illuminated on the dashboard
- Reduced engine performance
- Increased fuel consumption
- Possible rough idling or stalling
BMW DTC P118B causes
The potential causes of the DTC P118B on a BMW can vary, but some common reasons include:
- Faulty engine oil separator heating element
- Wiring or connector issues in the heating circuit
- Defective engine control module (ECM)
BMW DTC P118B seriousness
While the DTC P118B may not cause immediate drivability issues, it is important to address this fault promptly to prevent potential damage to the engine components and ensure optimal vehicle performance.
How to diagnose DTC P118B on BMW
To diagnose the DTC P118B on a BMW, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes stored in the vehicle’s ECM
- Inspect the engine oil separator heating circuit for any visible damage or loose connections
- Test the engine oil separator heating element for proper resistance
- Check the ECM for any related fault codes or issues
How to fix DTC P118B on BMW
Depending on the root cause of the DTC P118B, the following steps may be taken to fix the issue:
- Replace the faulty engine oil separator heating element
- Repair any damaged wiring or connectors in the heating circuit
- If the ECM is determined to be faulty, it may need to be replaced or reprogrammed
How to erase DTC P118B on BMW
After the underlying issue causing the DTC P118B has been resolved, the fault code can be cleared using a diagnostic scanner. This will reset the Check Engine Light and allow for a fresh monitoring of the vehicle’s systems.
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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