P20E8 - OBD II Trouble Code

Our automotive experts have put together the following information about the P20E8 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 P20E8 code.

OBD II Fault Code

• OBD II P20E8

OBD-II Code Powertrain Control Module (PCM) failure is defined as a Reductant Pressure Too Low

Diesel Exhaust Fluid (DEF) is used to assist in converting leftover exhaust particles to harmless gases. In order to burn off those particles, the temperature of the exhaust system needs to increase. the injection of DEF Fluid into the exhaust stream brings Diesel Particulate Filter (DPF) up to temperature. The system is then able to convert harmful NOx to Nitrogen, Carbon Dioxide, and water. The pressure of this system is monitored by the Reductant Pressure Sensor. If the system does not hold enough pressure, code P20E8 will be stored.

Powertrain Control Module (PCM) failure Symptoms

• DPF regeneration may not occur

Common Problems That Trigger the P20E8 Code

• Powertrain Control Module (PCM) failure
• Reductant pressure sensor failure
• Selective Catalytic Reduction (SCR) failure
• Wiring issue