BMW DTC P20C8 – Reductant Heater ‘D’ Control Circuit High
DTC P20C8 meaning on BMW
The Diagnostic Trouble Code (DTC) P20C8 for BMW refers to the ¨Reductant Heater ‘D’ Control Circuit High.¨ This code indicates that there is a high voltage condition detected in the control circuit of the Reductant Heater ‘D’. The Reductant Heater is a component of the Selective Catalytic Reduction (SCR) system, which helps reduce emissions by converting harmful nitrogen oxides into nitrogen and water vapor.
BMW DTC P20C8 symptoms
Symptoms of the BMW DTC P20C8 may include:
- Check Engine Light illuminated
- Reduced engine performance
- Possible decrease in fuel efficiency
BMW DTC P20C8 causes
Common causes of the BMW DTC P20C8 may include:
- Faulty Reductant Heater ‘D’
- Short circuit or open circuit in the control circuit
- Corrosion or poor connections in the wiring harness
- Defective SCR system components
BMW DTC P20C8 seriousness
The BMW DTC P20C8 should be addressed promptly as it can lead to increased emissions and potential regulatory compliance issues. Ignoring this code may result in reduced engine efficiency and performance.
How to diagnose DTC P20C8 on BMW
To diagnose the DTC P20C8 on a BMW, you can perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes and freeze frame data
- Inspect the Reductant Heater ‘D’ and its control circuit for any visible damage or corrosion
- Check the wiring harness and connectors for loose connections or shorts
- Test the Reductant Heater ‘D’ for proper resistance and functionality
How to fix DTC P20C8 on BMW
To fix the DTC P20C8 on a BMW, you can try the following solutions:
- Replace the faulty Reductant Heater ‘D’ if necessary
- Repair any damaged wiring or connectors in the control circuit
- Clean or replace any corroded connections in the system
- Reset the fault codes and perform a test drive to ensure the issue is resolved
How to erase DTC P20C8 on BMW
To erase the DTC P20C8 on a BMW, you can use a diagnostic scanner to clear the fault codes from the vehicle’s memory. After making the necessary repairs and confirming that the issue has been resolved, you can reset the codes to turn off the Check Engine Light.
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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