P20ED - OBD II Trouble Code

January 31, 2017

Our automotive experts have put together the following information about the P20ED diagnostic trouble code. We've provided the common symptoms that occur when this code is set along with the frequent repairs that address the issues related to the P20ED code.

OBD II Fault Code

  • OBD II P20ED

OBD-II Code Diagnostic Trouble Code is defined as an SCR nox Pre-Catalyst - Over Temperature

The engine computer (PCM) monitors the Reductant Catalyst System's use of DEF and its ability to convert NOx to Nitrogen, Carbon Dioxide, and Water. If the Reductant Catalyst fails to perform its job efficiently, code P20ED is set.

Diagnostic Trouble Code Symptoms

  • DPF regeneration may not occur

Common Problems That Trigger the P20ED Code

  • DEF contamination
  • DEF injector failure
  • Selective Catalytic Reduction (SCR) failure

About the Author

Brad Kava is an automotive expert at RepairPal, the leading online source of auto repair resources and estimates. With many ASE Master certified mechanics on staff who have decades of experience, RepairPal knows all the fine points of car repair.

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